Question

PLS HELP ! 100 POINTS!!!!! Select the correct answer. This graph represents a quadratic function. What is the value of a in the function’s equation?

Answer 1

A=3

Explanation:

I got it right on the test

Answer 2

a = 3

Explanation:

The vertex form of a quadratic is

y = a(x-h) ^2 +k where ( h,k) is the vertex

the vertex is (-2,2)

y = a(x- -2) ^2 +2

y = a(x+2) ^2 +2

Pick another point on the graph to determine a

(-1,5) and substitute into the equation

5 = a( -1+2) ^2 +2

5 = a(1)^2 +2

5 = a(1) +2

Subtract 2 from each side

5-2 = a+2-2

3 = a