Part A: W= Wage (money earned)
$6 (earned per hour without working overtime) Equation: W=$6x
x= number of hours
S= (money earned)
$6 plus $9 (earned per hour with working overtime) Equation S=$15y
y= hours
Part C: Use S=$15y (this shows the amount of money earned after working overtime after the certain amount of hours spent)
$330=$15y
I think you can solve from there