Question

On a coordinate plane, a parabola opens up. It goes through (negative 7.5, 4), has a vertex of (negative 3, negative 9), and goes through (1.5 4). Solid circles appear on the parabola at (negative 7, 1.75), (negative 6, negative 3), (negative 3, negative 9), (0, negative 3), (1, 1.75).
Which is f(–3) for the quadratic function graphed?

Answer 1

Answer:

f(-3) = -9.

Step-by-step explanation:

The equation of the curve in vertex form is:

f(x) = a(x + 3)^2 - 9     a is positive as the parabola opens up.

It passes through the point (1.5, 4), so

4 = a(1.5 + 3)^2 - 9

20.25a = 13

a = 13/20.25

a = 0.6420.

So the equation of the graph is

0.6420(x + 3)^2 - 9.

f(-3) = 0.6420(-3 + 3)^2 - 9

= 0.642*0 - 9.

= -9.