Question

Select the correct answer.
This graph represents a quadratic function.

Answer 1

a = - 1

Explanation:

given the zeros of a parabola x = a and x = b , then the factors are

(x - a) and (x - b) , then the equation is

y = a(x - a)(x - b) ← a is a multiplier

here the zeros are x = - 3 and x = 3 , then factors are

(x - (- 3) ) and (x - 3) , that is (x + 3) and (x - 3) and the equation is

y = a(x - 3)(x + 3)

to find a substitute any other point on the curve into the equation

using (0, 9 ) , then

9 = a(0 - 3)(0 + 3) = a(- 3)(3) = - 9a ( divide both sides by - 9 )

- 1 = a