can you explain or tell me why thats the answer

Answer:

B

Step-by-step explanation:

To make the perfect square the first step is  Subtract 40 from both sides option (A) is correct.

Any equation of the form [tex]\rm ax^2+bx+c=0[/tex]  where x is variable and a, b, and c are any real numbers where a ≠ 0 is called a quadratic equation.

As we know, the formula for the roots of the quadratic equation is given by:

[tex]\rm x = \dfrac{-b \pm\sqrt{b^2-4ac}}{2a}[/tex]

The complete question is:

Which is the best first step to solve 5x²+12x = 40 by completing the square?

We have a quadratic equation:

5x²+12x = 40

To make the perfect square:

First, subtract 40 from both sides.

5x²+12x - 40 = 40 - 40

5x²+12x - 40 = 0

Thus, to make the perfect square the first step is  Subtract 40 from both sides option (A) is correct.

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Answer: 7

Step-by-step explanation:

3x (4 - 2) + 1

3x (2) + 1

6 + 1

7

Answer:

equation

Step-by-step explanation:

obviously!

Answer:

$2.64

Step-by-step explanation:

I hoped I could help you!!

Answer: Few phrases make me cringe the way I do when I hear, “Ours is not to reason why; just invert and multiply.” A student’s job in math class is to reason, and a teacher’s job is to help the students see that math makes sense. Understanding division of fractions is complicated, bringing together many ideas that build up to a method that makes sense, especially in the tricky case of a fraction divided by a fraction. Liping Ma writes about research asking teachers to explain what it means to divide by a fraction. Most U.S. teachers were startled to find how difficult this was for them. What if we start with the simpler case of a whole number divided by a fraction?

Answer:

[tex]\left\{\begin{matrix}2p + 4c = 31.50\\3p + 2c = 33.25\end{matrix}\right.[/tex]

Step-by-step explanation:

Let's call (as suggested)

p = the cost of one pizza

c = the cost of one cheeseburger

The Anderson Family ordered 2 pizzas and 4 cheeseburgers and paid $31.50, thus:

2p + 4c = 31.50             [1]

Next weekend, they ate at the same restaurant and ordered 3 pizzas and 2 cheeseburgers for $33.25, thus:

3p + 2c = 33.25           [2]

To know the cost of one pizza and one cheeseburger, we need to solve the system of equations defined by [1] and [2]

[tex]\left\{\begin{matrix}2p + 4c = 31.50\\3p + 2c = 33.25\end{matrix}\right.[/tex]

Answer:

Combine the like terms

-4x+2

Thats it

i really dont know but good luck

Answer:

Pink: 0.33

Yellow: 0.22

Blue: 1.67

Green: 0.28

Step-by-step explanation:

Total of Jelly Beans: 36

Pink: [tex]\frac{12}{36}[/tex] = 0.33

Yellow: [tex]\frac{8}{36}[/tex] = 0.22

Blue: [tex]\frac{6}{36}[/tex] = 1.67

Green: [tex]\frac{10}{36}[/tex] = 0.28

9514 1404 393

Answer:

  a = 57.5

  b = 90

  c = 65

Step-by-step explanation:

The measure of an inscribed angle is half that of the arc it intercepts. The angle at 'a' intercepts an arc of 115°, so its measure is (115/2)° = 57.5°

__

The inscribed angle at 'b' is a semicircle, 180°, so the measure of 'b' is (180/2)° = 90°.

__

The arc 'c' is the remainder of a semicircle after 115° have been taken away. Its measure is 180° -115° = 65°.

  (a, b, c) = (57.5, 90, 65)

Answer:

x = - 2

Step-by-step explanation:

Step 1:

-2 ( x + 11 ) = - 18         Equation

Step 2:

- 2x - 22 = - 18       Multiply

Step 3:

- 2x = 4       Add 22 on both sides

Step 4:

x = 4 ÷ - 2

Answer:

x = - 2

Hope This Helps :)

Answer:

B.) 10 cm squared

Step-by-step explanation:

Answer:

ensure that no single branch of government would have too much power

Step-by-step explanation:

Answer:

1 x=12

Step-by-step explanation:

combine -2 ans -2 then add -8 the subtract 5 from 4 and divde 1 from each side

Answer:

Sure, I can try to help.

Step-by-step explanation:

Answer:

The discrimination is positive

Step-by-step explanation:

The graph shows the parabola with branches go up in positive y-direction. This gives you that a>0.

Since parabola has two x-intercepts, then the equation  has two different solutions and the discriminant is greater than 0.

Answer:

10% of choosing a 7th grade boy.

50% of choosing 8th grade boy

Step-by-step explanation:

Answer:

Step-by-step explanation:

prob(boy 7th grade)= 1/10  it is just one boy out of 10 students

prob(boy 8th grade)= 3/6=1/2  there are 3 boys out of 6 students

Prob(both boys)=( 1/10)*(1/2)=1/20

Answer:

A. 2.10b + 12.99 = 21.39; 4 bottles

Step-by-step explanation:

The b represents bottles of water, at the end of the equation. If each bottle is $2.10, and there were 4 bottles brought, $2.10 * 4 = $8.40, and $8.40 + $12.99 is $21.39.

Answer:

Multiply by 18

Step-by-step explanation:

Given

[tex]\frac{x}{3} + \frac{x}{6} = \frac{11}{9}[/tex]

Required

Eliminate the fraction

To eliminate the fraction, we first determine the LCM of the denominators (3, 6 and 9)

This is show below:

List out the multiplies of 3, 6 and 9

[tex]3 = 3,6,9,12,15,18,21,24,27,30...[/tex]

[tex]6 = 6,12,18,24,30...[/tex]

[tex]9 = 9,18,27...[/tex]

The least common multiple is 18.

Hence, when both sides of the equation is multiplied by 18, the fraction is eliminated;

See proof

[tex]18 * (\frac{x}{3} + \frac{x}{6}) = \frac{11}{9} * 18[/tex]

[tex]\frac{18x}{3} + \frac{18x}{6} = \frac{11*18}{9}[/tex]

[tex]6x + 3x = 11 * 2[/tex]

[tex]6x + 3x = 22[/tex]

The fraction is eliminated

Answer: 10 , 10

Step-by-step explanation:

By solving one-step matrix equation, we get [tex]x_{1} =10[/tex], [tex]x_{2}=10[/tex].

A matrix equation is an equation of the form Ax = b , where A is an m × n matrix, b is a vector in R m , and x is a vector whose coefficients x 1 , x 2 ,..., x n are unknown.

A one-step equation is an algebraic equation you can solve in only one step. You've solved the equation when you get the variable by itself, with no numbers in front of it, on one side of the equal sign.

Given one-step matrix equation

[tex]\left[\begin{array}{c}x_{1} &x_{2} \end{array}\right]+\left[\begin{array}{c}-2 &5 \end{array}\right] =\left[\begin{array}{c}8 &15 \end{array}\right][/tex]

By adding the matrix the respective equations are:

[tex]x_{1} +(-2)=8[/tex].....(1)

[tex]x_{2} +(5)=15[/tex].....(2)

By solving [tex]x_{1} +(-2)=8[/tex]

⇒ [tex]x_{1} -2=8[/tex]

Add 2 on the both sides of the equation

⇒ [tex]x_{1}-2+2 =8+2[/tex]

⇒ [tex]x_{1} =8+2[/tex]

⇒ [tex]x_{1} =10[/tex]

Solving equation 2

[tex]x_{2} +(5)=15[/tex]

⇒ [tex]x_{2} +5=15[/tex]

Subtract 5 on both sides of the equation

⇒ [tex]x_{2} +5-5=15-5[/tex]

⇒ [tex]x_{2}=10[/tex]

By solving one-step matrix equation, we get [tex]x_{1} =10[/tex], [tex]x_{2}=10[/tex].

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Answer:

y = 3x + 3 using a

{-2, 1, 2}

Step-by-step explanation:

Answer:

Step-by-step explanation:

3 x 4 - 5

= 7

The required output of the given function at x = 4 is given as f(x) = 7.

The process in mathematics to operate and interpret the function to make the function or expression simple or more understandable is called simplifying and the process is called simplification.

Here,
To evaluate output from the function f(x) = 3x - 5, at x = 4 we must put the value of x in the function:
f(4) = 3(4) - 5
f(4) = 7

Thus, the required output of the given function at x = 4 is given as f(x) = 7.

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Answer:

35 homeruns

Step-by-step explanation:

583*0.06=349.8-->34.98-->35

Answer:

The LA Dodgers hit 35 homeruns approximately in the league in year 2014.

Step-by-step explanation:

Given that:

Percentage of homeruns hit by LA Dodgers = 6% of the entire League

Total homeruns hit in the league = 583 homeruns

Homeruns hit by LA Dodgers = [tex]\frac{6}{100}*583[/tex]

Homeruns hit by LA Dodgers = 0.06 * 583

Homeruns hit by LA Dodgers = 34.98

Hence,

The LA Dodgers hit 35 homeruns approximately in the league in year 2014.

Answer:

18c - 30d + 36

Step-by-step explanation:

Answer:

0

Step-by-step explanation:

f(-4) means x = -4 so then plug -4 into the function.

y = -4²-16

y = 0

Answer:

f(-4) =0

Step-by-step explanation:

f(x)=x²-16

Let x = -4

f(-4) = (-4)^2 -16

       =  16-16

       = 0