# What is the vertex form of #y=(x – 8)(x + 5) #?

##### 1 Answer

Jul 10, 2017

Vertex form is

#### Explanation:

Start by multiplying out.

#y = x^2 - 3x - 40#

Now complete the square.

#y = 1(x^2 - 3x + 9/4 - 9/4) - 40#

#y = 1(x^2 - 3x + 9/4) - 9/4 - 40#

#y = 1(x - 3/2)^2 - 169/4#

Hopefully this helps!