Both rates are same when you divide them. 80/12= 6.6667 and 60/9= 6.667.
So, 6.6667 is the rate for each minute
Answer: f(x) and g(x) are inverses of each other
<u>Step-by-step explanation:</u>
To find the inverse of a function, swap the x's and y's and then solve for "y"
f(x) = 5x + 2
y = 5x + 2
Swap:
x = 5y + 2
<u> -2 </u> <u> - 2 </u>
x - 2 = 5y
<u>÷5 </u> <u>÷5 </u>

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Put the numbers in the given equation and solve for k.
... $11 = k·(8 €)
Divide by the coefficient of k:
... k = $11/(8 €) = 1.375 $/€
Then your equation is ...
... y = (1.375 $/€)x
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It is fairly common to leave the units out of such equations, assuming that everyone understands that x is in euros and y is in dollars and the conversion factor includes a unit change from euros to dollars. Thus, you might expect to see ...
... y = 1.375·x