Practice with
Isosceles Triangles

Topic Index | Geometry Index | Regents Exam Prep Center

Answer the following questions dealing with isosceles triangles.

1.

   Find x:
                

Choose one:
 52
32
20

 

 

2.

 
If a triangle is equilateral, then it is isosceles.
TRUE or FALSE?

Choose one:
TRUE
FALSE

 

 

3.

   Find the measure of <1:
  
(assume all segments are straight)
                       
      

Choose one:
 32.5
50
65

 

 

4.

   Find the measure of angle x:
     (assume all segments are straight)
                       
      

Choose one:
 56
68
112

 

 

5.

   Find the measure of angle y.
                

Choose one:
 48
84
96

 

 

6.

If a triangle is isosceles, then it is also equilateral.
TRUE or FALSE?

Choose one:
TRUE
FALSE

 

Please note:  The answers shown for the following problems represent ONE possible solution.
Other solutions and methods of presentation are possible.

7.

 


Explanation

 

 

 

 

8.

In ,  the vertices have coordinates
A(0,-8),
B(10,16),
C(-24,2).
Show whether this triangle is isosceles or not isosceles.


Explanation

 

 

9.



Explanation



Express AB in terms
of r and t

Is triangle ABC an isosceles triangle?


 

 

 

 

 

11.

Prove:  The bisector of the vertex angle of an isosceles triangle is perpendicular to the base.

Explanation