# What is the vertex of # y= x^2 - 4x- 15#?

##### 1 Answer

Jan 2, 2016

(2 , -19 )

#### Explanation:

this is a quadratic function of the form

here a = 1 and b = -4

the x-coordinate of the vertex can be found using x = - b/2a

x = -( -4/2 )= 2

and y =

y = 4 - 8 -15

y = -19