Answer:
a) f(x-1) = 2x^2-11x-1
b) x = -1.5 or 5
Step-by-step explanation:
a) To get f(x-1)
We proceed to substitute x-1 for x as follows
f(x-1) = 2(x-1)^2 -7(x-1) -10
f(x-1) = 2(x^2 - 2x + 1) -7(x-1)-10
f(x-1) = 2x^2 -4x + 2 -7x + 7-10
f(x-1) = 2x^2-11x-1
b) What we have to do here is substitute 5 for f(x) and solve for x
5 = 2x^2 -7x-10
2x^2 -7x -10-5 = 0
2x^2 - 7x - 15 = 0
2x^2 -10x + 3x -15 = 0
2x(x-5) + 3(x-5) = 0
(2x + 3)(x-5) = 0
2x + 3 = 0 or x -5 = 0
2x = -3 or x = 5
x = -3/2 or x = 5
x = -1.5 or 5
