SOLUTION: if f(x)=2x and g(x)=x-4 what is the value of f[g(3)]

Question 653229: if f(x)=2x and g(x)=x-4 what is the value of f[g(3)]
Answer by Shana-D77(132) (Show Source): You can put this solution on YOUR website!
if f(x)=2x and g(x)=x-4 what is the value of f[g(3)]?
f[g(3)] says "f at g at 3". More specifically, it reads, "evaluate g if x is 3, then stick whatever number you get into the x in the f function". Always work inside to outside in these functions within functions.
So:
g(x) = x - 4
g(3) = 3 - 4
g(3) = -1
Now put -1 into f.
f(x) = 2x
f(-1) = 2(-1)
f(-1) = -2
So f[g(3)] = -2
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