Questions on Algebra: Linear Algebra (NOT Linear Equations) answered by real tutors!

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Question 166496: I am lost on how to do to problems
1. f(x)=3x and g(x)=4x-3, find f[g(5)] and g[f(5)].
2. find the inverse of f(x)=7x-2.
Can you please help. I must show my work. These are from a worksheet. We have no textbook to use.
Thanks
: I am lost on how to do to problems
1. f(x)=3x and g(x)=4x-3, find f[g(5)] and g[f(5)].
2. find the inverse of f(x)=7x-2.
Can you please help. I must show my work. These are from a worksheet. We have no textbook to use.
Thanks

Answer by stanbon(19743) About Me  (Show Source):
You can put this solution on YOUR website!
1. f(x)=3x and g(x)=4x-3, find f[g(5)] and g[f(5)].
----
f[g(5)] = f[4*5-3] = f[17] = 3*17 = 51
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2. find the inverse of f(x)=7x-2.
1st: Interchage x and y to get:
x = 7y-2
2nd: Solve for y to get the inverse:
y = (1/7)x + (2/7)
======================
Cheers,
Stan H.