Answer :
Answer: 10 hours
Explanation:
Let x be the number of hours Lee spent in working at the movie theater and y be the she spent in working in her aunt's store.
Given : Lee worked a total of 30 hours at two jobs last week.
Also, Her combined pay from the jobs was $240. She earned $9 per hour working at the movie theater and $6 per hour working in her aunt's store.
Then the required system of equation will be
[tex]x+y=30[/tex] (1)
[tex]9x+6y=240[/tex] (2)
Divide equation (2) by 3 on both sides
[tex]3x+2y=80[/tex] (3)
Multiply 2 to the equation (1) on both sides , we get
[tex]2x+2y=60[/tex] (4)
Eliminate equation (4) from (3), we get
[tex]x=20[/tex]
Put x= 0 in (1), we get
[tex]20+y=30\\\\\Rightarrow\ y=30-20=10[/tex]
Hence, she spent 20 hours in movie theater and 10 hours in her aunt's store last week.