# Math Help - similar triangles

2. ## Re: similar triangles

Hello, vegasgunner!

We have 30-60-90 right triangles.

Code:
B o   1
*  *   D
*60   o
*    *_  *
2 *   *√3     * 3
*30*           *
* *               *
** 60             30  *
C o  *  *  *  *_ *  *  *  o A
2√3
Knowing the $1\text{-}2\text{-}\sqrt{3}$ ratios of the sides,
We can let $BD = 1$ and determine the lengths of all the segments.

Now you can calculate the areas of the triangles and their ratio.

3. ## Re: similar triangles

Note that the two acute angles are "complementary", they add to 90 degrees. Now notice that one of the acute angles in the "large" triangle is also an angle in one of the two smaller triangles.

4. ## Re: similar triangles

one side and one angle of both the trianles are common and both are right angled so its from sas its complementary.