The lowest oxygen index in the aquarium is found at the location (5, 5) in the xy plane, where the oxygen index value is -192.
To compute the absolute extrema values of the oxygen index function in the region, we need to evaluate the function at its critical points and at the boundary points.
1: Find the critical points:
To find the critical points, we need to find the values of x and y where the partial derivatives of the oxygen index function are equal to zero.
∂(oxygen index)/∂x = 1 - 9y = 0 ---> y = 1/9
∂(oxygen index)/∂y = 1 - 9x = 0 ---> x = 1/9
So, the critical point is (1/9, 1/9).
2: Evaluate the function at the boundary points:
We need to evaluate the oxygen index function at the boundary points (0,0), (5,0), (0,5), and (5,5).
At (0,0):
oxygen index = 1 + 0 - 9(0)(0) + 27 = 1 + 0 + 0 + 27 = 28
At (5,0):
oxygen index = 1 + 5 - 9(5)(0) + 27 = 1 + 5 + 0 + 27 = 33
At (0,5):
oxygen index = 1 + 0 - 9(0)(5) + 27 = 1 + 0 + 0 + 27 = 28
At (5,5):
oxygen index = 1 + 5 - 9(5)(5) + 27 = 1 + 5 - 225 + 27 = -192
3: Compare the function values:
Now, we compare the function values at the critical point and the boundary points to find the absolute extrema.
Critical point: (1/9, 1/9) → oxygen index = 1 + (1/9) - 9(1/9)(1/9) + 27
= 1 + 1/9 - 1/9 + 27
= 28
Boundary points:
- Lowest oxygen index: (5,5) → oxygen index = -192
- Highest oxygen index: (5,0) → oxygen index = 33
Therefore, the location in the aquarium with the lowest oxygen index is at coordinates (5, 5).
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Please help I'm begging a ACE OR GENES To help me please please help please please ASAP please please help please please ASAP please please help
Answer:
3/2
Step-by-step explanation:
WX/AB = 12/8 = 3/2
Answer: 3/2
ill put this up for 50 just please someone help me.
Answer:
1) Let the dimensions be x for greater size and 1 for unit size
Product is:
x² + 3x + 2x + 6 = x² + 5x + 6Factors are:
(x + 3) and (x + 2)2)
Product is:
2x² + 3x + 2x + 3 = 2x² + 5x + 3Factors are:
(2x + 3) and (x + 1)Darius wants to buy a new car. The car he chooses has a total purchase price of $18,500. Darius uses a multi-offer website to apply for a car loan. He receives three offers with minimum payments he can afford. The terms for each loan are shown in the table.
Darius belive he should chose loan option B. Which of the following statements about Darius’s choice is true?
A. Darius should choose loan option B because it has the shortest loan term.
B. Darius should not choose loan option B because he will pay $398.52 more in interest than on loan option C.
C. Darius should choose loan option B because he will pay $280.44 less in interest than on loan option A.
D. Darius should not choose loan option B because it does not have the lowest interest rate.
Answer:
the correct answer is B, Darius should not choose loan option B because he will pay $398.52 more in interest than on loan option C.
Step-by-step explanation:
I also had this question, and it showed that I got it correct :)
You are interested in estimating the thic THCurwis of the local adult population of female white-tailed deer (doe). From past data, you estimate that the standard deviation of all adult female white-tailed deer in this region to be 18 pounds. What sample size would you need to in order to estimate the mean weight of all female white-tailed deer, with a 90% confidence level, to within 5 pounds of the actual weight?
The sample size required to estimate the mean weight of all female white-tailed deer with a 90% confidence level within 5 pounds of the actual weight is 43.
In order to estimate the sample size required to estimate the mean weight of all female white-tailed deer with a 90% confidence level within 5 pounds of the actual weight, the following steps are to be followed:
Step 1: Determine the confidence level and the maximum allowable error
The given confidence level is 90%.
The maximum allowable error is 5 pounds.
Step 2: Determine the population standard deviationThe population standard deviation is given as σ = 18 pounds.
Step 3: Determine the critical value
The critical value corresponding to a 90% confidence level is 1.645.
Step 4: Calculate the sample size formula to calculate the sample size is given as
n = [(z-value)² × σ²] / E² Where n = sample size
z-value = critical value
σ = population standard deviation = maximum allowable error
Substituting the given values in the above formula, we get,n = [(1.645)² × (18)²] / (5)²= 42.68≈43 (approx)
Therefore, the sample size required to estimate the mean weight of all female white-tailed deer with a 90% confidence level within 5 pounds of the actual weight is 43. Answer: 43
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Which of the following is one solution to the expression (ax + b)(cx - d) = 0 ?
A. −b
B. d
C. −b/a
D. −d/c
Solve the equation −6 +x/4 = −5
Pls help
Answer:
x=4
Step-by-step explanation:
Answer:
x = 4
Step-by-step explanation:
-6 + x/4 = -5
-6+6 + x/4 = -5+6
x/4 = 1
x/4 *4 = 1*4
x = 4
hope this helped :)
plssss help
use the property that it says to solve the proportion ty
Answer:
the answer is 45 over 6
Step-by-step explanation:
A shortcut is "2 x _____ is 6", which is 3.
Multiply 15 by 3 also, to get 45,
45/6
Aliyah spent half of her weekly allowance playing arcade games. To earn more money her parents let her mow the lawn for $7. What is her weekly allowance (W) if she ended up with $16? The variable should always go in the first term
Answer:
who mows the lawn for 7 dollars :/
Step-by-step explanation:
What is the greatest common factor of 42 and 50
The greatest common factor of 42 and 50 is 2.
The given numbers are 42 and 50
The greatest common factor (GCF) of two numbers is the largest number that divides both of them evenly.
To find the GCF of 42 and 50,
We can start by listing the factors of each number.
The factors of 42 are 1, 2, 3, 6, 7, 14, 21, and 42.
Similarly, the factors of 50 are 1, 2, 5, 10, 25, and 50.
By comparing the factors,
We can see that the highest common factor is 2.
Therefore, the GCF of 42 and 50 is 2.
This means that 2 is the largest number that can divide both 42 and 50 without leaving a remainder.
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The sum of the first nine terms in a sequence is 49,205. Each term is 3 times the previous term. What is the third term?
Answer:
a₃ = 32 805Step-by-step explanation:
Each term is 3 times the previous term:
r = 3
The sum of the first nine terms in a sequence is 49,205:
[tex]S_n=a_1\cdot\dfrac{1-q^n}{1-q}\\\\\\49205=a_1\cdot\dfrac{1-3^9}{1-3}\\\\49205=a_1\cdot\dfrac{1-19683}{-2}\\\\49205=a_1\cdot9841\\\\a_1=5[/tex]
What is the third term?
[tex]a_n=a_1\cdot q^{n-1}\\\\a_3=5\cdot3^8=32805[/tex]
The equation for a parabola has the form y=az? + bz +c, where a, b, and care constants and a 70. Find an equation for the parabola that passes through the points (-1,0), (1,6), and (-3,-14). Answer: y = __
The equation for the parabola that passes through the points (-1,0), (1,6), and (-3,-14) is y = -2x² + 3x + 1.
To find the equation of a parabola, we need to substitute the given points into the general form of the equation, y = az² + bz + c, and solve for the unknown constants a, b, and c. In this case, we have three points: (-1,0), (1,6), and (-3,-14). We can plug in the x and y values of each point into the equation to obtain three equations.
For the point (-1,0):
0 = a(-1)² + b(-1) + c
For the point (1,6):
6 = a(1)² + b(1) + c
For the point (-3,-14):
-14 = a(-3)² + b(-3) + c
Now we have a system of three equations with three unknowns (a, b, and c). Solving this system will give us the values of a, b, and c, which we can then substitute back into the general equation to obtain the specific equation of the parabola.
To solve the system, we can use various methods such as substitution, elimination, or matrices. However, to keep the explanation concise, I'll provide the solution directly.
Solving the system of equations, we find:
a = -2b = 3c = 1Substituting these values back into the general equation, we get:
y = -2x² + 3x + 1
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Question 1[16 marks] Consider the following optimisation problem max f(x, y) = t √ x y, subject to tx^2 + y ≤ 5, x ≥ 0, y ≥ 0.
a) Solve the problem for t = 1.
b) State and explain the content of the envelope theorem.
c) What is the marginal effect on the solution if the constant t is increased?
(a) Optimization problem: The optimization problem is shown below:
max f(x, y) = t √ x y, subject to tx² + y ≤ 5x ≥ 0y ≥ 0
Solving the problem for t = 1,t = 1f(x,y) = √xytx² + y ≤ 5x ≥ 0y ≥ 0.
The Lagrangian function for this problem is:
L(x, y, λ) = t √ xy + λ(5 - tx² - y)
We set the partial derivative of L with respect to x to zero:
∂L/∂x = t(0.5√y)/√x + (-2λtx) = 0
We then obtain:
(1) 0.5t√y/√x = 2λtxIf we set the partial derivative of L with respect to y to zero, we obtain:
(2) 0.5t√x/√y + λ(-1) = 0
Multiplying both sides by (-1), we obtain:
(3) -0.5t√x/√y = λ We set the partial derivative of L with respect to λ to zero, we obtain:
(4) 5 - tx² - y = 0Substituting Equation (3) into Equation (1), we obtain:
(5) 0.5t√y/√x = -2(5 - tx² - y)x
Substituting Equation (5) into Equation (4), we obtain:
(6) 5 - tx² - 2x²(5 - tx² - y)² = 0
After expanding Equation (6), we obtain a fourth-order equation in y. Solving this equation leads to:(7) y = 5 - tx²/3
We then substitute y into Equation (3) to obtain: x = 5/2t²From Equation (7), we obtain: y = 5 - tx²/3=5-5/3*2.5=2.7778
(b) Envelope theorem
According to the Envelope Theorem, the marginal effect of a parameter on an optimal solution is equal to the partial derivative of the optimal value with respect to that parameter. This means that if a parameter changes slightly, the change in the optimal value can be estimated using the first-order approximation. (c) Increasing the constant tIf we increase the constant t, the optimal x and y will also increase. This is because an increase in t will lead to a higher value of f(x, y).
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Find the value of x that makes the quadrilateral a parallelogram.
6x
3x + 2
X=
Answer:
15
Step-by-step explanation: simple math
Answer:
2/3
Step-by-step explanation:
6x = 3x+2
3x = 2
x = 2/3
A company is designing a new cylindrical water bottle the volume of the bottle by 204 cm the height of the water bottles 8.9 cm3 what is the radius of a water bottle use 3.14 for pie
Answer:
2.70cm
Step-by-step explanation:
Given data
Answer:
2cm
Step-by-step explanation:
Given data
Capacity/volume= 204 cm
Height= 8.9 cm
Required
The radius r
let us apply the expression for the volume of a cylinder
V=πr^2h
204=πr^2*8.9
204=3.14r^2*8.9
r^2= 204/27.946
r^2=7.30
r= √7.30
r=2.70cm
Hence the radius is 2.70cm
The covariance of random variables X, Y is defined as Cov(X,Y) = E[(X – Ux)(Y – My)] where Úx = E(X) and My = E(Y). Note: Var(X) = Cov(X,X).
(d) Show that [E(XY)]? < E(X)E(Y). Hint: Let Z=X+ay,
We have shown that [E(XY)]^2 < E(X)E(Y), as required.
To show that [E(XY)]^2 < E(X)E(Y), we can follow the hint provided and introduce a new random variable Z = X + aY, where 'a' is a constant.
First, let's expand the expression E(XY) using the law of iterated expectations:
E(XY) = E[E(XY|Z)]
Now, substituting Z = X + aY into the conditional expectation:
E(XY) = E[E(X(X + aY)|Z)]
= E[E(X^2 + aXY|Z)]
Expanding the inner expectation:
E(XY) = E[X^2 + aXY]
Next, let's square both sides of the inequality to be proved:
[E(XY)]^2 < E(X)E(Y)
(E[X^2 + aXY])^2 < E(X)^2E(Y)^2
Expanding the square:
E(X^2)^2 + 2aE(X^2)E(XY) + a^2E(XY)^2 < E(X)^2E(Y)^2
Since E(X^2) is the variance of X (Var(X)), we can rewrite it as:
Var(X) + [E(X)]^2
Using the covariance formula, Cov(X,Y) = E[(X - Ux)(Y - My)], we can rewrite the second term as:
Cov(X,Y) + [E(X)][E(Y)]
Substituting these expressions back into the inequality, we have:
Var(X) + [E(X)]^2 + 2a(Cov(X,Y) + [E(X)][E(Y)]) + a^2[E(XY)]^2 < E(X)^2E(Y)^2
Simplifying the equation, we have:
Var(X) + 2aCov(X,Y) + a^2[E(XY)]^2 < 0
This inequality holds true since the left-hand side of the equation is a quadratic expression in 'a' and the coefficient of the quadratic term is positive (Var(X)). Since the inequality holds for all values of 'a', it must hold when 'a' is zero. Therefore, we have:
Var(X) + 0 + 0 < 0
Which is not possible, thus proving that [E(XY)]^2 < E(X)E(Y).
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Please help meee! I will give brainleiest!
Answer:
64? I'm not sure but because if 1= girls (8 girls) and boys is 8 times more you do 8x8 I think sorry if I'm wrong
Answer:
There are 64 boys
Step-by-step explanation:
If there are 8 girls it would be 8*1
so you would have to multiply 8 by the ratio of boys which is 8*8
which equals 64 boys to 8 girls (8:1)
Your welcome
Find the surface area of the prism. Whoever solves this will guarantee get Brainliest Answer!!!
To find the total surface area of a prism, you need to calculate the area of two polygonal bases, i.e., the top face and bottom face. And then calculate the area of lateral faces connecting the bases. Add up the area of the two bases and the area of the lateral faces to get the total surface area of a prism.
Hope this helps!
HA
2
-X
- 2
2
-2
-4
A.
ys1
B.
1 sys 6
Oc.
y21
D.
all real numbers
Answer:
Can you please explain this question more thoroughly?
Step-by-step explanation:
it is difficult to understand
The simplified expression is 4x - 23.
Option A is the correct answer.
We have,
To simplify the expression 3(2x - 5) - 2(x + 4), we need to apply the distributive property and combine like terms.
First, distribute the 3 to the terms inside the parentheses:
3 * 2x = 6x
3 * (-5) = -15
Next, distribute the -2 to the terms inside the parentheses:
-2 * x = -2x
-2 * 4 = -8
Now, let's simplify the expression by combining like terms:
6x - 15 - 2x - 8
Combine the x terms: 6x - 2x = 4x
Combine the constant terms: -15 - 8 = -23
Thus,
The simplified expression is 4x - 23.
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The complete question:
Simplify the expression 3(2x - 5) - 2(x + 4).
A. 4x - 23
B. 4x - 7
C. 4x + 13
D. 4x + 7
mark+is+shopping+during+a+computer+store’s+20%+sale.+he+is+considering+buying+computers+that+range+in+cost+from+$500+to+$1000.+how+much+is+the+least+expensive+computer+after+the+20%+discount?
The least expensive computer after the 20% discount would be $400.
To calculate the price of the least expensive computer after the 20% discount, we need to find 20% of the original price and subtract it from the original price.
Let's assume the original price of the least expensive computer is x. The discount of 20% can be calculated as 0.20 * x. To find the discounted price, we subtract the discount from the original price: x - 0.20 * x = 0.80 * x.
Since we know that the cost of the least expensive computer ranges from $500 to $1000, we can substitute x with $500 and calculate the discounted price: 0.80 * $500 = $400. Therefore, the least expensive computer after the 20% discount would be $400.
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Test for a significant change in the attitude toward increased federal funding for stem cell research, as measured on an ordinal scale survey, before and after 22 people hear a discussion of the issue on a network news program.
The steps to test for a significant change in the attitude toward increased federal funding for stem cell research.
As measured on an ordinal scale survey, before and after 22 people hear a discussion of the issue on a network news program are as follows:
Step 1: State the null and alternative hypotheses
In this case, the null hypothesis states that there is no significant change in attitude towards increased federal funding for stem cell research before and after 22 people hear a discussion of the issue on a network news program. The alternative hypothesis states that there is a significant change in attitude towards increased federal funding for stem cell research before and after 22 people hear a discussion of the issue on a network news program.
Step 2: Set the level of significance
The level of significance, denoted by alpha, is the probability of rejecting the null hypothesis when it is true. A common level of significance is 0.05. This means that there is a 5% chance of rejecting the null hypothesis when it is true.
Step 3: Calculate the test statistic
To calculate the test statistic, we can use the Wilcoxon signed-rank test. This test compares the scores before and after the treatment and calculates the difference between them. The Wilcoxon signed-rank test is used for paired samples or repeated measures. It is a nonparametric test and is used when the data is not normally distributed or when the data is ordinal.
Step 4: Determine the critical value
To determine the critical value, we need to look up the value in the Wilcoxon signed-rank table. The critical value is the smallest value that would lead to the rejection of the null hypothesis.
Step 5: Compare the test statistic to the critical value
If the test statistic is greater than the critical value, we reject the null hypothesis. If the test statistic is less than the critical value, we fail to reject the null hypothesis.
Step 6: Interpret the results
If we reject the null hypothesis, we can conclude that there is a significant change in attitude towards increased federal funding for stem cell research before and after 22 people hear a discussion of the issue on a network news program. If we fail to reject the null hypothesis, we cannot conclude that there is a significant change in attitude towards increased federal funding for stem cell research before and after 22 people hear a discussion of the issue on a network news program.
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The ordinal scale survey is the type of scale utilized for the measurement of attitude, and it is used to rank the participant's responses on an order (ordinal) from smallest to greatest.
The survey measured the attitude toward increased federal funding for stem cell research, and it was conducted on 22 people before and after a discussion on the issue on a network news program.
A statistical analysis of the survey responses can be conducted using the Wilcoxon Signed Rank Test to test for a significant change in attitude.
The Wilcoxon Signed Rank Test is an ideal nonparametric test that tests for changes in attitudes before and after a discussion on the issue on a network news program.
The Wilcoxon Signed Rank Test compares the scores of each participant's responses on the ordinal scale before and after the discussion.
After computing the differences between the scores, the test ranks the differences, and then the sum of the positive and negative ranks is calculated.
The calculated sum is then compared with the Wilcoxon Signed Rank Test critical values, which depend on the number of pairs tested, which in this case, is 22.
If the calculated sum is higher than the critical value, then there is a significant change in attitude towards increased federal funding for stem cell research after the discussion on the network news program.
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Calculate the value of (6.9x10^-3)x(2x10^9) Give your answer in standard form.
A car dealership offers two types of discounts.
• Discount 1: Take 5% off the original price of a car built last year and then receive a
$3,500 rebate.
• Discount 2: Take 10% off the original price of a car built this year and then receive a
$1,250 rebate.
A customer is deciding between two cars.
• Car R was built last year and has an original price of $25,340.
• Car S was built this year and has an original price of $22,860.
Based on this information, which statement is true?
A The customer would pay $19,324 for Car S.
B The customer would pay $24,073 for Car R.
C The customer would pay $21,824 for Car S.
D The customer would pay $23,107 for Car R.
Answer:
The customer would pay $19,324 for Car S.
Step-by-step explanation:
Take Car S
$22,860 x .1 (ten percent) = $2,286
$22,860 (original car price) - $2,286 (minus the 10%) = $20,574 (new car price)
$20,574 - rebate of $1,250 = $19,324
The customer would pay $19,324 for Car S.
All other do not come out but this one does, so that is the only option for this!
What is the main cause of tides?
A.
Earth's gravitational pull
B.
the moon's gravitational pull
C.
the moon's rotation around its axis
D.
Earth's revolution around the sun
The main cause of tides is the moon's gravitational pull.
Hope it helps you...
Answered by Benjemin ☺️
✅
IM GIVING BRAINLIEST!!PLEASE HELP!!
Answer:
D
Step-by-step explanation:
(x - 3)(x + 4) = x^2 + x - 12
You put the names of all the students in your class in a paper bag. There are 14 boys and 20 girls. If you draw a name at random, what is P(boy’s name)?
Answer:
7/17
Step-by-step explanation:
you add the number of students which is 34. Then you take the number of boys and put it over 34 which would be 14/34. when you reduce it the answer will be 7/17.
let me know if this helps!
Let T be a linear transformation from P2 to R², defined by T(p) = [p(0) p(1)] polynomial p(t) in P2. Find bases for kernel of T and range of T.
For the linear transformation we have:
Basis for the kernel of T (Ker(T)): {[t² - t]}
Basis for the range of T (Range(T)): {[1, 1], [1, 0], [0, 1]}
How to find the bases for kernel of T and range of T?To find the bases for the kernel and range of the linear transformation T: P2 -> R², defined by T(p) = [p(0), p(1)], we need to understand the properties of T and solve for the appropriate vectors.
Kernel of T (Nullspace):
The kernel of T, denoted as Ker(T), consists of all polynomials p in P2 such that T(p) = [p(0), p(1)] = [0, 0]. In other words, the kernel contains all polynomials that get mapped to the zero vector in R².
Let's solve for the kernel by setting up the system of equations:
p(0) = 0
p(1) = 0
Since we are dealing with polynomials of degree at most 2, let's consider a general polynomial p(t) = at² + bt + c.
Substituting into the equations:
(0)a + (0)b + c = 0 -> c = 0
(1)a + (1)b + c = 0 -> a + b = 0 -> b = -a
Thus, any polynomial of the form p(t) = at² - at, where a is a scalar, will be in the kernel of T. Therefore, a basis for the kernel is [t² - t].
Range of T:
The range of T, denoted as Range(T), consists of all vectors in R² that can be obtained by applying the linear transformation T to some polynomial in P2.
To find the range, we need to determine all possible outputs of T(p) for polynomials p in P2.
Let's consider a general polynomial p(t) = at² + bt + c and apply T(p):
T(p) = [p(0), p(1)] = [a(0)² + b(0) + c, a(1)² + b(1) + c] = [c, a + b + c]
So, any vector [x, y] in the range of T must satisfy x = c and y = a + b + c for some a, b, c.
In R², any vector [x, y] can be written as [x, y] = [c, a + b + c] = c[1, 1] + a[1, 0] + b[0, 1], where a, b, c are scalars.
So, the basis for the range of T is {[1, 1], [1, 0], [0, 1]}.
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1. Write the following function using unit step functions and then find its Laplace transform: 0
The Laplace transformation in the given function is = 5 - 8e⁻⁷ˣ/ x
Rewrite f in terms of the unit step function:
f(t) = { y = 5 for 0 ≤ t ≤ 7
= { x = - 3 t > 7
f(t) = 5{u(t) -u(t -7) - 3u (t -7)}
= 5u(t) - 8u (t-7)
Recall the time-shifting property of the Laplace transform:
L I u(t - c)f(t -c) I
= e⁻ᵃˣ L[f(t)]
and the Laplace transform of a constant function,
L(K) = k/a
So we have
L{f(t)} = 5u(t) - 8u (t-7)
= 5 L[1] - 8e⁻⁷ˣ
= 5 - 8e⁻⁷ˣ/ x
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The given question is incomplete, the complete question is below
Write the following function using unit step functions and then find its Laplace transform:
f(t) = { y = 5 for 0 ≤ t ≤ 7
= { x = - 3 t > 7
PLEASE HELP!!!! Jul is using the graph of an exponential function to represent the value of an investment where x is the number of years Jul has owned the investment. Which statement correctly describes a key feature of the function?
Answer: the answer is D
Step-by-step explanation:
Trust me
the domain of the function is x greater than equal to 0.
Answer: The domain of the function is x>0. So D just took the test, got it right!
Step-by-step explanation:
What is the solution to the system of equations graphed below?
a. (2,-3)
b. (-3,2)
c. (-2,3)
d. (3,-2
plz help i’m in a timed test
Two angles in a triangle have measures of 18 and 77º.
What is the measure of the third angle
Answer:
85 ° is the answer to the question
Answer:
85 degrees
Step-by-step explanation:
Angles in a triangle add up to 180 in total so to solve it add the two angles you know so 18+77 which is 95 than you subtract it from 180 so 180 - 95 is 85