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 ?
To find the missing length of the rectangular prism, we need to first calculate the total surface area of the prism using the given dimensions.
The formula for the surface area of a rectangular prism is:
Surface Area = 2(lw + lh + wh)
Given:
Height = 9 cm
Width = 9 cm
Surface Area = 432 cm^2
Substitute the given values into the formula:
432 = 2(l*9 + 9*9 + 9l)
432 = 2(9l + 81 + 9l)
432 = 2(18l + 81)
432 = 36l + 162
270 = 36l
l = 7.5 cm
Therefore, the missing length of the rectangular prism is 7.5 cm.