Question

Function f(x) = a(x+1)(x-3) has a vertex at (1, -16). Find a

Answer 1

• a = 4

Explanation:

Given

• f(x) = a(x+1)(x-3)
• Vertex = (1, -16)

To find

• Value of a

Solution

Substituting he coordinates:

• -16 = a(1 + 1)(1 - 3)
• -16 = a(2)(-2)
• -16 = -4a
• a = 4