what is the missing length of a rectangular prism where the height and width are both 9 cm and the surface area is 432 cm ^2?

To find the missing length of the rectangular prism, we need to use the formula for the surface area of a rectangular prism:

Surface Area = 2lw + 2lh + 2wh

Given that the height and width are both 9 cm, we can substitute these values into the formula:

432 = 2(x)(9) + 2(9)(9) + 2(9)(x)

Now, simplify the equation:

432 = 18x + 162 + 18x

432 = 36x + 162

270 = 36x

x = 7.5 cm

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