What is the vertex form of y= (3-x)(3x-1)+11 ?

1 Answer
May 2, 2016

y = -3(x-5/3)^2+49/3

Explanation:

The vertex form of a quadratic equation is y = a(x-h)^2+k. In this form, we can see that the vertex is (h, k).

To put the equation in vertex form, first we'll expand the equation, and then use a process called completing the square.

y=(3-x)(3x-1)+11

=> y = -3x^2+9x+x-3+11

=> y = -3x^2+10x+8

=> y = -3(x^2-10/3x)+8

=> y = -3(x^2-10/3x+(5/3)^2-(5/3)^2)+8

=> y = -3(x^2-10/3x+25/9)+(-3)(-25/9)+8

=> y = -3(x-5/3)^2+49/3

So, the vertex form is y = -3(x-5/3)^2+49/3 and the vertex is (5/3,49/3)