What is the vertex form of y= 3x^2-15x-14 ?

1 Answer
Mar 14, 2018

y=3(x-5/2)^2-131/4

Explanation:

"the equation of a parabola in "color(blue)"vertex form" is.

color(red)(bar(ul(|color(white)(2/2)color(black)(y=a(x-h)^2+k)color(white)(2/2)|)))

"where "(h,k)" are the coordinates of the vertex and a"
"is a multiplier"

"to obtain this form use "color(blue)"completing the square"

• " the coefficient of the "x^2" term must be 1"

rArry=3(x^2-5x-14/3)

• " add/subtract "(1/2"coefficient of the x-term")^2" to"
x^2-5x

y=3(x^2+2(-5/2)xcolor(red)(+25/4)color(red)(-25/4)-14/3)

color(white)(y)=3(x-5/2)^2+3(-25/4-14/3)

color(white)(y)=3(x-5/2)^2-131/4larrcolor(red)"in vertex form"