What are the roots of the quadratic equation x²-81=0

Answer:

Nu știu scuze

Step-by-step explanation:

Answer:

The total profits will be zero at sales prices of $4 and $9

Step-by-step explanation:

∵ The function is y = -3x² + 39x - 108, where

The zeroes of the function are the values of x at y = 0

→ To find the zeroes of the function above equate y by 0

∵ 0 = -3x² + 39x - 108

→ Switch the two sides

∴ -3x² + 39x - 108 = 0

→ Divide all terms by -3 to simplify the equation

∴ x² - 13x + 36 = 0

→ Let us factor the trinominal into two brackets

∵ The last term is +ve and the middle term is -ve

∴ The two brackets have (-) sign in the middle ⇒ (... - ...)(... - ...)

∵ x² = (x)(x)

∵ 36 = (4)(9)

∵ (4)(x) + (9)(x) = 4x + 9x = 13x ⇒ the value of the middel term

→ That means the factors of the trinomial are (x - 4) and (x - 9)

∴ x² - 13x + 36 = (x - 4)(x - 9)

→ Replace the trinomial by its factors

∴ (x - 4)(x - 9) = 0

→ Equate each bracket by 0 to find x

∵ x - 4 = 0

→ Add 4 to both sides

∴ x = 4

∵ x - 9 = 0

→ Add 4 to both sides

∴ x = 9

∴ The zeroes of the functions are 4 and 9

∵ x represents the sales price in dollars

∴ The sales prices which make zero profit are $4 and $9

∴ The total profits will be zero at sales prices of $4 and $9

Answer:

4:1

Step-by-step explanation:

Let the no. of goals Daniel scored be x

Hence,

No. of goals Joaquin scored = 4 x

No. of goals Daniel scored = x

Hence,

The ratio of the no. of goals scored by Joaquin to the no. of goals scored by Daniel

[tex]=\frac{4x}{1x}[/tex]

[tex]=\frac{4}{1} \\=4:1[/tex]

Answer:

see below

Step-by-step explanation:

f(0) means x=0

We use the f(x) when x<5

f(0) = 0+4 = 4

f(6) means x=6  

We use the f(x) when 5≤x<7

f(6) =8

Answer:

Relation

Step-by-step explanation:

The rule that relates elements of one set to elements of another set is called "Relation". Functions are special types of Relations.

Answer:

7.25

Step-by-step explanation:

if you want to know what 1 box would be you would divide 14.50 by 2 to get 7.25 i’m sorry if i did this wrong

Answer:

12x -11

Step-by-step explanation:

Lets start by applying the 2/3 to the two values in the parenthesis. Doing so will yield: 4x -7 +8x -4. We can simplify this to be 12x -11

Answer:

15 ( for Herimone) And 8 ( For Stranger Things)

Step-by-step explanation:

When Herimone uses 5 grams of Pearl Sheen she creates 30 fluid ounces of love potion. Last week she created 90 ounces which is 3 times larger than 30 ounces so you have to multiply 5 by 3 to figure out the amount of Pearl Sheen she used which is 15

For stranger things they Multiplied 3 by 2 so you have to multiply 1 by 2 to get 2. Then you have to add 6 and 2 to get 8 kids.

Hope This Helps!

Answer:

8.75 as 80-73 gives 7 and 7/80x 100= 8.73 by which is the percentage it is decreased.

Answer:

well 3 × 7 = 21

Step-by-step explanation:

1. 0+3=3

2. 3+3=6

3. 6+3=9

4. 9+3=12

5. 12+3=15

6. 15+3=18

7. 18+3=21

So the answer is 7

Answer:

y = -4x + 5

Step-by-step explanation:

The equation for the line, in slope-intercept form will take the following equation format which is y = mx + b.

Where,

b = y-intercept = 5 (this is where the line intercepts the y-axis, and also, x = 0 here)

m = [tex] \frac{y_2 - y_1}{x_2 - x_1} [/tex]

Use any two points on the line. Using (0, 5) and (1, 1), calculate m as follows:

m = [tex] \frac{1 - 5}{1 - 0} = \frac{-4}{1} = -4 [/tex]

Substitute m = -4, and b = 5 into y = mx + b.

y = -4x + 5

Answer:

Y=-4x+5

Step-by-step explanation:

Answer:

Step-by-step explanation:

If there are 48 books on shelves

Then number of books in 12 shelves

= 48 ÷ 12 = 4 books

Answer:

576

Step-by-step explanation:

because 48 books on each shelves 48×12=576

Answer:

7t-4=10t+14

7t-10t=14+4

-3t=18

-3t/3=18/-3

t=-6

Answer:

Pretty sure it's t = -6

Step-by-step explanation:

7t - 4 = 10t + 14

7t -10t = 14 + 4

-3t = 18

t = -6

Answer:

I think its 4 but not 100% sure.

264-10=16+52

Add 10 to both sides

264=16+62

subtract 16 from both sides

248=62

Divide and i got 4.

Answer:

121.92 cm cubed

Step-by-step explanation:

all you have to do is multiply all 3 measurements to find the simple shapes volume, and then convert to centimeters using the simple 2.54 cm=1 in conversion rate

Answer:

1/36 cubic ft

Step-by-step explanation:

4 inches = 12/3 inches = 1/3 ft

2 inches = 12/6 inches = 1/6 ft

6 inches = 12/2 inches = 1/2 ft

Answer:

so you need the value for the 20% right ?

Step-by-step explanation:

Answer:

An alternative definition for the acceleration ax that can be written in terms of [tex]v_x[/tex] and [tex]\frac{dv_x}{dx}[/tex] is [tex]a_x=v_x \frac{dv_x}{dx}[/tex]

Step-by-step explanation:

We know that :

[tex]a_x=\frac{dv_x}{dt}[/tex]

Now we are supposed to find an alternative definition for the acceleration ax that can be written in terms of [tex]v_x[/tex] and [tex]\frac{dv_x}{dx}[/tex]

So, We will use chain rule over here :

[tex]a_x=\frac{dv_x}{dt}\\a_x=\frac{dv_x}{dt} \times \frac{dx}{dx}\\a_x=\frac{dv_x}{dx} \times \frac{dx}{dt}\\a_x=\frac{dv_x}{dx} \times \frac{dx}{dt} [\frac{dx}{dt}=v_x]\\a_x=\frac{dv_x}{dx} \times v_x\\a_x=v_x\frac{dv_x}{dx}[/tex]

Hence an alternative definition for the acceleration ax that can be written in terms of [tex]v_x[/tex] and [tex]\frac{dv_x}{dx}[/tex] is [tex]a_x=v_x \frac{dv_x}{dx}[/tex]

The alternative definition for the acceleration ax that can be written in terms of vx and dx/ dx is [tex]a_x = v_x \frac{dv_x}{dx}[/tex]

Here we used the chain rule:

It is the basic method for differentiating a composite function. Here the first factor on the right, Df(g(x)), represents that the derivative of f(x) is first found and then x, wherever it arises, is replaced by the function g(x).

So,

[tex]a_x = \frac{dv_x}{dt}\\\\ = \frac{dv_x}{dt} \times \frac{dx}{dx}\\\\= \frac{dv_x}{dx} \times \frac{dx}{dt}\\\\ = \frac{dv_x}{dx} \times \frac{dx}{dt} (\frac{dx}{dt} = v_x)\\\\ = \frac{dv_x}{dx} \times v_x\\\\= v_x\frac{dv_x}{dx}[/tex]

Learn more about time here: https://brainly.com/question/11325462

Answer:

1 = No     2 = Yes      3 = 1.88

Step-by-step explanation:

Answer:

1. Yes 2. No 3. = 1.88 .

Step-by-step explanation:

1. Possibly yes, the first table represents a proportional relationship because cost per pound of apples is the same in each row, 1.88 dollars per pound.

2. Definitely no, the second table does not represent a proportional relationship because cost per topping is not the same in each row. (An equation is =1.50+8.99 but students do not need to provide an equation.)

3. An equation relating the cost to pounds of apples is = 1.88.

Answer:

1+1 is 2 and 2+3 is 5

Step-by-step explanation:

Answer:

16 times

Step-by-step explanation:

i could give an explanation if needed

y = 1/3x +b

1 = 1/3(9) +b

1 = 3 +b

subtract 3 from both sides

-2 = b

Answer:

A

Step-by-step explanation:

plug the points into the slope formula

slope = (y2 - y1)/(x2 - x1)  Then you get the slope of -0.5

(5 - -1))/(-6-6)

6/-12

-0.5

Plug a point in to the equation of y = -0.5x + b

-1 = -0.5(6) +b

2 = b

Answer:

7. move to the right by 4 units and down by 5 units

8. just rotate it to the left side (180 degrees is a flat line in the opposite direction)

9. reflection is pretty easy, just pretend you are folding your paper in half. so just redraw it on the other side in the opposite direction (fold paper sideways)

Step-by-step explanation:

Answer: 1st, 2nd, and 3rd option are correct :) ✨

Step-by-step explanation:

Answer:

A, B, C

Step-by-step explanation:

Answer:

11. f(g(3))=5 g(f(-2))=-6

12.f(g(3))=8 g(f(-2))=3

13.f(g(3))=8 g(f(-2))=3

14.f(g(3))=0  g(f(-2))=5

Step-by-step explanation:

Answer:

62 large cups were sold

Step-by-step explanation:

88*1.25=110

265-110=155

155/2.50=62

Answer:

0?

Step-by-step explanation:

Answer:

$7.20

Step-by-step explanation:

$36.00 for 5 items.

Divide $36.00 by 5 to find the price of 1 item.

$36/5 = $7.20