What is the lateral area of a square pyramid with side length 11.2 cm and slant height 20 cm?

224 cm2
448 cm2
896 cm2
2508.8 cm2

Question

What is the lateral area of a square pyramid with side length 11.2 cm and slant height 20 cm? 

224 cm2
448 cm2
896 cm2
2508.8 cm2

anonymous · Answer

I tried the formula and I don't get any of the answers.

anonymous · Answer

I get 40 but that's not an available answer.

anonymous · Answer

Is the side length the  slant height?

anonymous · Answer

What do you mean?

anonymous · Answer

|dw:1366924952628:dw|

anonymous · Answer

|dw:1366925047621:dw|

anonymous · Answer

OH NEVER MIND I READ THE QUESTION INCORRECTLY..
Sorry bout that

anonymous · Answer

$$LA=\frac{ 1 }{ 2 }(p)(slant height)$$

anonymous · Answer

So I have to find the perimeter first.

anonymous · Answer

The perimeter of the pyramid is found by adding all of the side lengths..

So basically it is:
11.2+11.2+11.2+11.2

which equals

44.8

anonymous · Answer

Okay, so 22.4 * 20?

anonymous · Answer

= 224cm^2!

anonymous · Answer

Thanks :)

anonymous · Answer

You're welcome (:

anonymous · Answer

Actually, I should've been a little more patient. If you plug in (1/2)(44.8)(20), you get 448. I'm changing that real quick.