Question

A rectangular prism has a surface area of 400 cm 2. If it is 10 cm long and 10 cm wide, what is its height?

4 cm
5 cm
8 cm
40 cm

Answer 1

it is 5 cm............

Answer 2

`area = 2(wl + hl + hw) \\ height = ( (a)/(2) - lw)/(l + w) \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = ( (400)/(2) - 10 * 10)/(10 + 10) \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 5cm`

hope this helps you...