Answer:
5x + 70 = 320
Explanation:
We know that Carmine paid an electrician a certain amount per hour, we also know that they worked for 5 hours. Therefore we have 5x.
He also got paid 70 for parts, meaning an extra $70
And we know that we have the total charge and that the main point of this question is to determine how much the electrician was paid per hour.
Therefore :
5x + 70 = 320