Isosceles Triangle Theorem Worksheet
Explore and apply the Isosceles Triangle Theorem to find unknown angles and side lengths in isosceles triangles for Grade 8 math.
Includes
Standards
Topics
Isosceles Triangle Theorem
Name:
Date:
Score:
Read each question carefully and answer to the best of your ability. Show all your work for short answer questions.
1. In your own words, state the Isosceles Triangle Theorem.
2. What is the converse of the Isosceles Triangle Theorem?
3. If two sides of a triangle are congruent, then the angles those sides are congruent.
adjacent to
opposite
between
outside
4. In triangle ABC, if AB = AC and angle BAC = 50°, what are the measures of angle ABC and angle ACB?
5. If angle X = 70° and angle Y = 70° in triangle XYZ, then the side opposite angle X, which is , is congruent to the side opposite angle Y, which is .
6. An isosceles triangle has a perimeter of 30 cm. If the base measures 10 cm, what is the length of each of the congruent sides?
7. All equilateral triangles are also isosceles triangles.
True
False