Vertex form:
y-k=a(x-h)^2
h=-2,k=-20,y=-12 when x=0
thus;
-12+20=a(0+2)^2
8=4a
a=2
Equation:
y+20=2(x+2)^2
y+20=2(x^2+4x+4)
f(x)=2(x^2+4x+4)-20
f(x)=2x^2+8x+8-20
f(x)=2x^2+8x-20

4 0

4 years ago

Read 2 more answers

If a figure is a triangle, then it has three sides.

stellarik [79]

This answer is true

3 0

3 years ago

What are the coordinates of the x-intercepts of the parabola y = x² - 8x + 15?

tamaranim1 [39]

Answer:

(3, 0) and (5, 0)

Step-by-step explanation:

we have

$y=x^{2}-8x+15$

we know that

The x-intercepts are the values of x when the value of y is equal to zero

For y=0

$x^{2}-8x+15=0$

The formula to solve a quadratic equation of the form

$ax^{2} +bx+c=0$

is equal to

$x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$x^{2}-8x+15=0$

$a=1\\b=-8\\c=15$

substitute in the formula

$x=\frac{-(-8)\pm\sqrt{-8^{2}-4(1)(15)}} {2(1)}$

$x=\frac{8\pm\sqrt{4}} {2}$

$x=\frac{8\pm2} {2}$

$x=\frac{8+2} {2}=5$

$x=\frac{8-2} {2}=3$

x=3, x=5

therefore

The x-intercepts are (3,0) and (5,0)

4 0

3 years ago

Javon spent %687 on pokemon cards. Energy cards cost $6 and dragon cards cost $5. If he bought a total of 127 packs then how man

pshichka [43]

Answer:

Javon purchase Energy cards = 52

Javon purchase Dragon cards = 75

Step-by-step explanation:

Given - Javon spent $687 on pokemon cards. Energy cards cost $6

and dragon cards cost $5.

To find - If he bought a total of 127 packs then how many of each did he buy ?

Proof -

Let Javon purchase Energy cards = x

Javon purchase Dragon cards = y

Now,

Given that he bought a total of 127 packs

⇒x + y = 127

Also,

Cost for 1 Energy card = $6

⇒Cost of x Energy cards = $ 6x

And

Cost of 1 Dragon card = $5

⇒Cost of y Dragon card = $ 5y

Now,

Given that Javon spent $687 on pokemon cards.

⇒6x + 5y = 687

∴ we get

x + y = 127 ..................(1)

6x + 5y = 687 .................(2)

Multiply by 6 in equation (1) , we get

6(x + y) = 6(127)

⇒6x + 6y = 762 .................(3)

Now,

Subtract equation (2) from equation (1) , we get

6x + 6y - (6x + 5y )= 762 - 687

⇒6x + 6y - 6x - 5y = 75

⇒y = 75

Now,

Put the value of y in equation (1), we get

x + 75 = 127

⇒x = 127 - 75

⇒x = 52

∴ we get

Javon purchase Energy cards = x = 52

Javon purchase Dragon cards = y = 75

3 0

3 years ago