To earn money for college, Avery works two part-time jobs: A and B. She earns $12 p er h o u r w or kin g a t j o b A an d an u nkn o w nam o u n t,$ x $d o ll a rs p er h o u r, w or kin g a t j o b B . I n o n e w ee k, A v erye a r n e d a t o t a l o f$ 240 for working at the two part-time jobs. The graph above represents all possible combinations of numbers of hours Avery could have worked at the two jobs to earn $240. T h e x - a x i sre p rese n t s h o u rs w or k e d a t J o b A, an d t h ey - a x i sre p rese n t s h o u rs w or k e d a t J o b B . T h e l in ese g m e n t co nn ec t s t h e p o in t s$ (20,0) $an d$ (0,15) $. Wha t i s t h e v a l u eo f$ x $?$