surface area help!

[simpsonlauren11]

i have to find the surface area of a rectangular pyrimad. base is 18 on all sides, and their is a hight of 41. HELP !

 

[galactus]

Why not just Google it?. There's plenty out there.

But, the formula is \(\displaystyle S=\frac{1}{2}\cdot \text{perimeter}\cdot \text{side length}\cdot \text{base area}\)

Since the base is 18' wide, then it's area is easy to find.

The side length can be found by using Pythagoras and half the base length, which forms a triangle.

\(\displaystyle \text{side length}=\sqrt{9^{2}+41^{2}}\)

Now, continue?.