Two Questions of Triangles and Apothem

• Apr 3rd 2012, 12:17 AM
Proclivitas
Two Questions of Triangles and Apothem
Attachment 23508
How do I find the area for this? Not looking for a complete solution, just the formula ;)

Also, second question, I'm giving the areas of two octagons, 81 and 144, and asked to find the ratio of their apothems, how do I do that?
• Apr 3rd 2012, 12:26 AM
princeps
Re: Two Questions of Triangles and Apothem
Quote:

Originally Posted by Proclivitas
Attachment 23508
How do I find the area for this? Not looking for a complete solution, just the formula ;)

Also, second question, I'm giving the areas of two octagons, 81 and 144, and asked to find the ratio of their apothems, how do I do that?

Area of triangle

Area of octagon
• Apr 3rd 2012, 12:49 AM
Proclivitas
Re: Two Questions of Triangles and Apothem
Quote:

Originally Posted by princeps

Doesn't really help me much since there is terminology which I don't understand.
• Apr 3rd 2012, 12:54 AM
biffboy
Re: Two Questions of Triangles and Apothem
There is a formula which says that if you know 2 sides of a triangle and the angle in between those sides then
the area = 1/2 of one side times the other times the sine of the angle, that is 1/2absinx
If two similar shapes have sides ( or any other similar line measurements) in the ratio p:q then the areas will be in the ratio p^2:q^2. Here you are given the ratio of the areas so can work back to ratio of lengths. The ratio of volumes would be p^3:q^3