Respuesta :

5 < 3h + 2 < = 11
subtract 2 from the left, center and right
3 < 3h < = 9
divide by 3 on the left, center, and right
1 < h < = 3
5 < 3h+2 <= 11
⇒ 5-2 < 3h <= 11-2
⇒ 3 < 3h <= 9
⇒ 1 < h <=3

Hope it helps!

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