Question

y = x2 - 6x - 8 Complete the square in the quadratic equation in order to write the equation in vertex form.

Answer 1

y = (x-3)^2 - 17

Explanation:

To complete the square, take the middle term bx and divide it in two. Then take the square.

x^2 - 6x - 8 has bx = -6x. Take -6/2 = -3. Square -3^2 = 9.

Now to finish completing the square add 9 and subtract 9 from one side.

y = x^2 - 6x - 8

y = (x^2 - 6x +9) -9 - 8

y = (x-3)^2 - 17