# What is the vertex of #y=(x-4) (x+2)#?

##### 1 Answer

Apr 27, 2017

The vertex is

#### Explanation:

You have 3 options here:

**Option 1**

- Multiply out to get the usual form of
# y = ax^2 +bx+c# - Complete the square to get vertex form:
#y= a(x+b)^2 +c#

**Option 2**

You already have the factors.

- Find the roots , the
#x# -intercepts.#(y=0)# - The line of symmetry is halfway between, them this gives
#x# - Use
#x# to find#y# .#(x,y)# will be the vertex.

**Option 3**

- Find the line of symmetry from

Then proceed as for option 2.

**Let's use option 2 as the more unusual one.**

Find the

Find the midpoint between them:

Find the

The vertex is at