Surface Area Unit Test

4 of 154 of 15 Items

Question
What is the missing length of a rectangular prism where the height and width are both 9 cm and the surface area is 432 cm2 ?(1 point)
cm

1 answer

The formula for the surface area of a rectangular prism is 2lw + 2lh + 2wh.

Given that the height and width are both 9 cm, the surface area is 432 cm^2, and the missing length is represented by "l," we can set up the equation:

2(9)(l) + 2(9)(9) + 2(l)(9) = 432

18l + 162 + 18l = 432
36l + 162 = 432
36l = 270
l = 7.5

Therefore, the missing length of the rectangular prism is 7.5 cm.