SOLUTION: f(x)=k(2+x), find the value of k if f^-1(-2)= -3

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Question 1021063: f(x)=k(2+x), find the value of k if f^-1(-2)= -3
Found 2 solutions by josgarithmetic, robertb:
Answer by josgarithmetic(39617) About Me  (Show Source):
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
If f%5E%28-1%29%28-2%29=+-3, then it should be that f(-3) = -2 by a direct application of f on both sides.
==> f(-3) = k(2-3) = -k after substituting x = -3 into f(x) = k(2+x)
==> -k = -2
==> highlight%28k+=+2%29.