A square pyramid has a lateral surface area of 20 square yards. If the slant height is 2 yards, what is the total surface area of the pyramid???

Question

anonymous · Answer

Lateral surface area is the sum of the areas of the sides (triangular) but not the base. So the 4 triangles' areas add up to 20. The slant height is the height of the triangular side (not the height of the pyramid -- see the difference?) So you know the area of each triangle (calculate) and you know the height of each triangle. Get the length of the base, then the area of the base, then finish up.

anonymous · Answer

BUt i dont get how to find the area and the base measurnments

bahrom7893 · Answer

oh i can figure this out i think, workin on it

anonymous · Answer

k its due tommorow and its getting late sooo...

bahrom7893 · Answer

k workin on it gimme about 10-20 mins

anonymous · Answer

Use the formula for area of triangle: 1/2 * base * height. Area is known, height is known, so you can calculate base.

Okay? Come on, stop giving up. You can do this.

bahrom7893 · Answer

5*5 = 25; the total area is 45

bahrom7893 · Answer

is that answer correct?

anonymous · Answer

so the answer is 45??

bahrom7893 · Answer

Yeah well according to my calculations, u wanna see what i did?

bahrom7893 · Answer

leah go here: http://www.twiddla.com/493733 I will try explainin on a whiteboard

bahrom7893 · Answer

leah can u copy and paste the link above? i will draw it out. easier for both of us

anonymous · Answer

Wait a sec i gotta go do somthing

bahrom7893 · Answer

http://bahrom7893.files.wordpress.com/2011/02/solution-to-pyramid1.png?w=648 I uploaded the solution there