Question

Identify the quadratic function from the choices below whose parabola opens downward.
Answer

y = -5x + x2

y = 2x2 – 4x

y = x2 – 11x + 7

y = x – 2x2 + 9

Answer 1

please help me i need the answer

Answer 2

y = x – 2x2 + 9

Answer 3

the answer is the fourth formula, you can see that seeing the sign of the highest order of the equation
x^2 with plus sign before is open upward
-x^2 with minus is open downward

Answer 4

because the when it is in the form y=ax2 +bx+c
a is negative as a is -2