What is the vertex form of y=4x2+12x+9?

1 Answer
May 17, 2016

y=4(x+1.5)2

Explanation:

Given -

y=4x2+12x+9

Find the x,yco-ordinates of the vertex

x=b2a=122×4=128=1.5

At x=1.5;y=4(1.5)2+12(1.5)+9

y=4(2.25)18+9
y=918+9=0

Equation in vertex form -

y=a(xh)2+k
h = x- coordinate
k= y- coordinate
a= coefficient of x2
Then -

y=4(x(1.5))2+0
y=4(x+1.5)2