Mr. Williams is driving on a highway at an average speed of 50 miles per hour. His destination is 100 miles away. The equation d - 100 - 50t gives the distance d (in miles) that he has left to travel as a function of the time t (in hours) that he has
been driving. Write and interpret the inverse of this function (2 points per part).
a. Solve the equation for t by
filling in the empty spaces.
d = 100 - 50
Write the equation.
d-
100 = - 50t
Subtract 100 from both sides.
D-100/-50=t
Divide both sides by -50.
D/-50+2=t
Simplify the left side.
b. Use the inverse function to find the time that Mr. Williams has left to travel when he has driven 75 miles.