The inverse of the equation is f⁻¹(y) = (25 - y)/40.
Why time can not be negative ?
The value of time can not be negative because then we can do time travel.We can assume time to zero at any given point as it is not absolute.
According to the given question
The plumber charges 40 dollars for each hour and for each service call he charges additional 25 dollars.
∴ The equation that represents plumbers total charge is f(t) where t represents time in hour.
f(t) = 40t + 25.
Now to find inverse of this equation we can replace f(t) with y and solve for t which implies
y = 40t + 25
40t = 25 - y
t = (25 - y)/40.
Now t can replaced with f⁻¹(y)
f⁻¹(y) = (25 - y)/40
As value of time can not be negative his total should be more than 25 dollars.
Learn more about inverse equations here :
https://brainly.com/question/15529152
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