Question

The standard form of the equation of a parabola is y=1/2x^2-4x+21. What is the vertex form of the equation?
A) y=1/2(x+4)^2+21
B)y=1/2(x-4)^2+21
C)y=1/2(x-4)^2+13
D)y=1/2(x+4)^2+13

Answer 1

seems unlikely it is A or D
replace \(x\) by \(4\) and see if you get \(13\) or \(21\)