
Doug C. answered 03/12/25
Math Tutor with Reputation to make difficult concepts understandable
So x is the variable that represents the charge in $ per hour that is charged by the tech. Since he worked for 4 hours his total charge for labor was $4x. In addition he charged $127 for parts.
So the total charge can be represented by: 4x + 127. For example if he charged $2 per hour, then the charge would have been 4(2) + 127 = 135.
But we are told that the total charge was in fact $227. So the equation that models the problem:
4x + 127 = 227. Solving that equation for x will determine what the tech actually charged for each hour of work.
4x = 100 (subtraction property for equality, subtracting 127 from each side).
x = 100/4 (division property for equality, dividing both sides by the coefficient of x which is 4).
x = 25
Check:
For 4 hours of work at $25 for each hour, the labor charge is 4(25) = 100.
Add on the $127 for parts; total charge is $100 + $127 = $227.