For the quadratic function fx9x22 4 What is the vertex Axis

Solution

f(x)=9(x+2)^2 -4

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

we will have   vertex ( -2, -4)

axis of symmtery will be x= -2

since a > 0 it means it will give minimum value

Here   we are getting minimum value   y=-4 for x=- 2

to find   x intercepts we will plug y=0

0 = 9(x+2)^2 -4

we will add 4 both sides

4= 9(x+2)^2

divide by 9 both sides

4/9=(x+2)^2

apply square root we get

+/- 2/3 =x+2

so we will have

-2-2/3= x    or   -2 +2/3 =x

x=-8/3   or   -4/3   answers

To find y intercept plug x=0

y= 30

so y intercept is 30