SOLUTION: Find the linear function f that satisfies the given conditions. f passes through (2, -1) and the inverse of f passes through (9, 4).

Algebra ->  Linear-equations -> SOLUTION: Find the linear function f that satisfies the given conditions. f passes through (2, -1) and the inverse of f passes through (9, 4).       Log On


   

Question 706567: Find the linear function f that satisfies the given conditions.
f passes through (2, -1) and the inverse of f passes through (9, 4).
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Since the inverse of each function will contain (y,x) for any (x,y) of the other function, we can identify two other points for the two points given.

f contains (2,-1), so the inverse of f will contain (-1,2) in addition to the already given (9,4). We can now find the equation for f%5E%28-1%29. Slope is %289-%28-1%29%29%2F%284-2%29 or m=5. What about y intercept? y=mx+b, b=y-mx, so pick a point; b=4-5*9=-41. so f%5E%28-1%29=5x-41. Now you can find the original equation, f ?