He rented the pressure washer for 4 hours, given that the total bill was $86.
An algebraic expression is the combination of numbers and variables in expressing and solving a particular mathematical question. An equation is the equality of expressions.
Let x = total number of hours he rented the pressure washer
The total bill, which was $86, includes the flat fee of $50 plus $9 per hour of use.
Hence, the equation will be 50 + 9x = 86.
Solve for x.
50 + 9x = 86
9x = 86 - 50
9x = 36
x = 4
total number of hours he rented the pressure washer = 4
Learn more about algebraic expression and equation here: brainly.com/question/3927786
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