Kiran is solving for , and he uses these steps:

He checks his answer and finds that it isn't a solution to the original equation, so he writes “no solutions.” Unfortunately, Kiran made a mistake while solving. Find his error and calculate the actual solution(s).

Identify all values of that make the equation true.

Rewrite the rational function in the form , where and are constants.

Elena has a boat that can go 9 miles per hour in still water. She travels downstream for a certain distance and then back upstream to where she started. Elena notices that it takes her 4 hours to travel upstream and 2 hours to travel downstream. The river’s speed is miles per hour. Write an equation that will help her solve for .