Answer: f(x) = (x + 3)(x – 7)
Step-by-step explanation: Use "standard form" of the function and insert values given: vertex (2,-25) intercept point (7,0)
f(x) = a(x-h)² + k from vertex, h is 2 y is -25 from intercept, x is 7 f(x) is 0
to find a, 0 = a(7-2)² +(-25) 0 = a(7-2)² -25 add 25 to both sides
25 = a(5)² 25 = 25a 25/25 = a 1=a (seems useless but verifies implied "a"coefficient is 1)
f(x) = a(x-h)² + k solve to get the quadratic form
f(x) = (x-2)² -25 (x - 2)² is x² -4x +4
f(x) = x² -4x +4 -25 simplify
f(x) = x² -4x - 21 then factor
f(x) = (x + 3)(x - 7)
