Question

Find the vertex of the graph of the function.

f(x) = 4x2 + 24x + 32

(5, 4)

(-3, -4)

(-4, -3)

(4, 5)

Answer 1

Usually at -b/2a

Answer 2

1. notice it`s an upward parabola
4(x^2 + 6x + 8)
4(x^2 + 2*3*x + 9) - 4
4(x+3)^2 -4
so when is value min : when x+3 is zero so x = -3

now find the value of this expression by putting x = -3 and get y coordinate

Answer 3

Umm...I'm confused.

Answer 4

which step ?

Answer 5

I know you made the 3 negative but how can you get a y-coordinate?

Answer 6

f(-3) = 4(-3)^2 +24(-3) + 32
= 36 - 72 + 32
= -4

Answer 7

Duh. Oh okay. I get it! Thanks!!!!

Answer 8

I forgot all about plugging it in the f(x). Thanks again!

Answer 9

Welcome