Which of the following statements are true about the quadratic function f(x)=a(x-h)^2 +k that has no real zeros? Select all that apply.

Question

A- the value of a must be greater than one, so the graph is vertically stretched.
B- the value of h cannot be zero.
C - the values of a and k must have opposite signs.
D- if the value of a is positive, then the value of k is negative.
E- if the value of k is negative , then the value of a is negative.
F- the value of k cannot be zero.
G- if the value of a is positive, then the graph opens upward.

Answer 1

C- the values of a and k must have opposite signs.
D- if the value of a is positive, then the value of k is negative.
F- the value of k cannot be zero.
G- if the value of a is positive, then the graph opens upward.