sal charges a one-time service fee of $70 plus an additional $40 per hour. the electrician, charges $45 per hour plus an additional one-time service fee of $35.

Question

Set up and solve a system to find when both electricians have the same total charge for the same amount of time worked.

Answer 1

Let S be what Sal charges, then S=70+40t dollars where t is time in hours.

Similarly let E=35+45t dollars be the electrician's charges.

When they're the same:

70+40t=35+45t, 35=5t, so t=7 hours. Both S and E=70+280=35+315=$350.