f(x)=-2x^2+12x-22

Question

completing the square. Wrie function in vertex form

Answer 1

(1) y = -2(x²-6x ) - 22         (rewrite)

(2) y = -2(x²-6x+9) - 22      (take half the coeff of -6 (-3), square it, and add it to the expression

(3) y = -2(x²-6x+9) -22 + 18   (u essentially subtracted 18 in (2) so you have to undo it by adding 18)

(4) y = -2(x-3)² -4     (vertex form)