Question

How can I find the range of y = −x2 − 12x + 3

Answer 1

THis is a parabola that opens downward. Parabolas that open downward always have a maximum point. Look at the drawing to see:

The maximum point is also the vertex. Use \(-\frac{b}{2a}\) to get the x-value of the vertex. Then plug that in for x to get the y-value.