(Worth 16 pts!) what lengths could I use to make this prism have a surface area of 200!?

Answer:
5 by 5 by 7.5
Step-by-step explanation:
The surface area of a rectangular prism is given by the formula ...
A = 2(LW +H(L +W)
__
There are many ways to choose L, W, and H to give the desired area. One way is to arbitrarily choose L = W = 5, then we have ...
200 = 2(5·5 +H(5 +5))
200 = 20H +50 . . . . . . . simplify
150 = 20H . . . . . subtract 50
H = 7.5 . . . . . . divide by 20
Possible dimensions are ...
5 by 5 by 7.5