Question

What is the surface area of this rectangular prism that has 9 ft a width of 5 feet and a height of 7.5ft

Answer 1

To get your answer:

9 times 5 times two= 90
9 times 7.5 times two= 135
5 times 7.5 times two= 75

then add all of them together and you will get the surface area
90+135+75=300
you should have an answer of 300 feet²

Answer 2

Hi!

The equation to find the surface are of a rectangular prism is

(a = area
h = height
w = width
l = length)

a = 2(wl + wh + hl)
Put the values into the equation, and solve.
a = 2(5 · 9 + 5 · 7.5 + 9 · 7.5)
a = 2(45 + 37.5 + 67.5)
a = 2 · 150
a = 300

The surface area is 300ft.

Hope this helps!
-Peredhel