Find the x-intercepts of the parabola with vertex (-2,-8) and y-intercept (0,4).

(-2 -2sqrt(2/3),0)

(-2 +2sqrt(2/3),0)

Step-by-step explanation:

The vertex form of a parabola is

y= a(x-h)^2 +k

where (h,k) is the vertex

y = a(x--2)^2 -8

y = a(x+2)^2 -8

We can substitute the other point in to find a

4 = a(0+2)^2 -8

4 = a(2)^2 -8

4 = 4a-8

Add 8 to each side

4+8 = 4a-8+8

12 = 4a

Divide by 4

12/4 =4a/4

a=3

y = 3(x+2)^2 -8

To find the x intercepts, set y =0 and solve for x

0 = 3(x+2)^2 -8

Add 8 to each side

8 =3(x+2)^2 -8+8

8 =3(x+2)^2

Divide by 3

8/3 =3/3(x+2)^2

Take the square root of each side

±sqrt(8/3) = sqrt((x+2)^2)

±sqrt(8/3) = (x+2)

We know that sqrt(ab) = sqrt(a)sqrt(b)

±sqrt(4) sqrt(2/3) = (x+2)

±2 sqrt(2/3) = (x+2)

Subtract 2 from each side

-2 ±2sqrt(2/3) = (x+2)-2

-2 ±2sqrt(2/3) = x

(-2 -2sqrt(2/3),0)

(-2 +2sqrt(2/3),0)

$450 is the answer.

step-by-step explanation:

30% of 450 = 135

450-135=315

where is the diagram? shown below where? ?

step-by-step explanation: