Area of Rhombus

mikosangeleyes

New member
Joined
May 20, 2006
Messages
9
Hi, I really need help with this problem. I spent about an hour trying to figure it out but I can't seem to.

I have to find the area of a rhombus using the "(d<sub>1</sub> × d<sub>2</sub>)/2" formula - when you multiply the lengths of both diagonals (d<sub>1</sub> and d<sub>2</sub>) and divide the result by 2.

I have the side, which is 12, meaning that the perimeter is 48. What appears to be the smaller angle in the rhombus is 45 degrees, meaning the consecutive angle is 135 degrees since they are supplementary.

That is all the information that was given but I don't know how to get the diagonals since I can't use 30 60 90 or 45 45 90 or at least it appears I can. I was thinking using a trigonometric function, but I'm not sure how that will help or how to make it work.

Please help soon!
 
Has your class only covered the 45-45-90 and 30-60-90 triangles so far? No generalized trig stuff yet?

Thank you.

Eliz.
 
No we have learned cosine, sine, and tangent and things like that I just don't know how to apply it in this problem.
 
If you don't already have the result, you should easily be able to prove that the diagonals of the rhombus cross at right angles, so that the four small triangles formed by the diagonals are right triangles. Apply sines and cosines to those triangles to find the values of p/2 and q/2.

Eliz.
 
Top