Answer:
c(x) = 18
f(x) = 15
g(x) = 30
r(x) = 6
Step-by-step explanation:
x is a placeholder. All these questions are telling you to do is replace x with its numerical value.
c(x) = 2x+4 when x = 7 <-- This is telling you to replace x with 7 in the equation. So, literally...
2(7)+4
14+4
18
c(x) = 18
You do the same for the others.
f(x) = -3x , x = -5
-3(-5) = -15
g(x) = 10x - 10, x = 4
10(4) - 10 = 40 - 10 = 30
r(x) = -6x-6, x = -2
-6(-2) - 6 = 12 - 6 = 6
