Question 631551
Show that f(x)= -2x + 19 has the 
inverse of f^-1(x)= x-19/-2 by finding 
f^-1(f(x))
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f(x) = -2x+19
1st: Interchange x and y
x = -2y+19
2nd; Solve for "y":
-2y = x-19
f^-1(x) = (x-19)/(-2)
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Cheers,
Stan H.