Question

Please help i have no idea what im doing!

Answer 1

x represents hours of babysitting

y represents hours of music lesson

hours on babysitting: 11

hours on music lessons: 7

Explanation:

x+y=18

5x+12y=139

-5(x+y=18)

=-5x-5y=-90

(5x+12y=139) + (-5x-5y=-90)

7y=49

y=7

x+7=18

x=11