Whats the vertex form of y=x^2-20x+15
this looks like a parabola so:y=x^2 - 20x + 15 --> x^2 - 20x +15=y(x^2 -20x)=y - 15 --> (x - 10)^2=y - 15 +100 ( used complete the square)(x - 10)^2=y + 85