Given f(x) = -3x^2 -3x, find f(-6)

To find f(-6), plug -6 in for x in the function f(x).

f(-6) = -3(-6)^2 - 3(-6)
f(-6) = -3(36) + 18
f(-6) = -108 + 18
f(-6) = -90

Therefore, f(-6) = -90.