a. The first employer pays $7 per hour so if you you work four hours you will have gotten $28. You dont need a variable for hours since the problem already states that you work a four hour shift. The first equation is therefor
The second employer gives you 8$ in four hours since 2*4 = 8 but they also give you 35 cents for each delivery. The second equation is p=8+.35d
these equations make up your system.