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 first need to calculate the total surface area of the prism.
The surface area of a rectangular prism is given by the formula:
Surface Area = 2(length x width) + 2(length x height) + 2(width x height)
Given that the height and width are both 9 cm, we can substitute these values into the formula:
432 = 2(length x 9) + 2(length x 9) + 2(9 x 9)
Simplifying:
432 = 18length + 18length + 162
432 = 36length + 162
Rearranging the equation, we get:
36length = 432 - 162
36length = 270
length = 270 / 36
length = 7.5
Therefore, the missing length of the rectangular prism is 7.5 cm.