Question

Choose all of the following equations that have a vertex that is the maximum point of the parabola. More than one answer may be chosen.

y = −4x2 + 8x − 19

y = −x2 − 7x + 1

y = 8x2 − 6x + 128

y = 3x2 + 9x − 4

Answer 1

Parabolas with a negative coefficient in front of the x^2 term are concave down so those are the graphs with maximums.

Answer 2

So the first and second.