Answer:
He must need to work 13 hours or 14 hours for lifeguarding.
Step-by-step explanation:
Consider the provided information.
Let x represents the number of hours for babysitting.
y represents the number of hours for life-guarding.
In a given week, he can work at most 17 total hours and must
[tex]x+y\leq 17[/tex]
Juan is working two summer jobs, making $12 per hour babysitting and making $16 per hour lifeguarding. He must earn at least $240.
[tex]12x+16y\geq 240[/tex]
If Juan worked 3 hours babysitting,
Substitute x=3 in [tex]x+y\leq 17[/tex]
[tex]3+y\leq 17[/tex]
[tex]y\leq 14[/tex]
Thus, he can work at most 14 hours for lifegurading.
Substitute x=3 in [tex]12x+16y\geq 240[/tex]
[tex]12(3)+16y\geq 240[/tex]
[tex]36+16y\geq 240[/tex]
[tex]16y\geq 204[/tex]
[tex]y\geq 12.75[/tex]
Therefore, he must need to work 13 hours or 14 hours for lifeguarding.