You work at the local pool as a lifeguard and you also work in the snack bar. You earn $15 per hour lifeguarding and $8 per hour working in the snack bar. Last week you worked a total of 20 hours and earned $202.
a. Write an equation in standard form for the hours you worked.
b. Write an equation in standard form for the money you earned.
c. Graph both equations on the same coordinate plane.
d. Determine how many hours you worked as a lifeguard and how many hours you worked in the snack bar. Explain your reasoning.