Which of the following quadratic functions has a graph that opens downward?
Check all that apply.
Ay=2x-x^2
By= 1/3x^2-8x-13
Cy=2/3x^2-13x+5
Dy= -(3+x^2)
...?
Check all that apply.
Ay=2x-x^2
By= 1/3x^2-8x-13
Cy=2/3x^2-13x+5
Dy= -(3+x^2)