Choose all of the following equations that have a graph in which the parabola opens downward. More than one answer may be chosen.

y = 2x2 + 2x + 8

y = −4x2 + 8x − 19

y = 16x2 + 2x − 4

y = −x2 − 6x + 10

Question

Choose all of the following equations that have a graph in which the parabola opens downward. More than one answer may be chosen.

 y = 2x2 + 2x + 8

 y = −4x2 + 8x − 19

 y = 16x2 + 2x − 4

 y = −x2 − 6x + 10

aum · Answer

Each equation represents a vertical parabola.

If the coefficient of x^2 is positive, the parabola opens upward.
If the coefficient of x^2 is negative, the parabola opens downward.

anonymous · Answer

so a?