Question 678356
f(x)=7+2x is the same as saying y=7+2x.  To find the inverse 1.  solve for x (get x by itself). then 2.  Replace x with y and y with x.<P>
y = 7+2x ---> y-7 = 2x ---> (y-7)/2  = x ---> y = (x-7)/2   <P>
The inverse function represents the number of toppings given a final price (x).  For example if the pizza costs $11 then it has y=(11-7)/2 = 4/2 = 2 toppings.
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