find the height of rectangular box if it’s length is 16 feet it’s with is 9 feet and it surface area is 438 ft²

Question

this is a question from a hw set in my pre cal class

Answer 1

the area of the two bases is 16 x 9 x 2 = 288 ft sq

the sorrounding area is 9 x h x 2 + 16 x h x 2 = 438-288 = 150 ft sq where h the high of the box

18h+32h = 150  50h=150   --->>>>  h=150/50 = 3 feet

so height of the box is 3 feet