ISEE Upper Level Math : How to find if two acute / obtuse triangles are similar

Example Questions

Example Question #34 : Triangles

NOTE: Figures NOT drawn to scale.

Refer to the above two triangles.

What is ?

Insufficient information is given to answer the question.

Explanation:

Corresponding sides of similar triangle are proportional, so if

, then

Substitute the known sidelengths, then solve for :

Example Question #35 : Triangles

What is the perimeter of  ?

It cannot be determined from the information given.

Explanation:

By definition, since, , side lengths are in proportion.

So,

The perimeter of  is

.

What is  ?