Easton is working two summer jobs, making $18 per hour tutoring and $9 per hour clearing tables. Last week Easton worked 4 times as many hours tutoring as he worked hours clearing tables hours and earned a total of $162. Graphically solve a system of equations in order to determine the number of hours Easton worked tutoring last week, x, and the number of hours Easton worked clearing tables last week, y.