# Thread: Two Questions of Triangles and Apothem

1. ## Two Questions of Triangles and Apothem

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?

2. ## Re: Two Questions of Triangles and Apothem

Originally Posted by Proclivitas

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

3. ## Re: Two Questions of Triangles and Apothem

Originally Posted by princeps
Doesn't really help me much since there is terminology which I don't understand.

4. ## 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