Isosceles & Equilateral Triangles

Isosceles & Equilateral Triangles

Mrs. Felig Geometry 2020

Hint: Since this is an equilateral triangle, all the sides are the same!!! That means we can set the expressions for our unknown sides equal to 10.

Hint: What do each of the angles of an equilateral triangle have to be?

Multiple Choice

What do the angles in an equilateral triangle measure?

• 30, 60, 90
• 60, 60, 60
• 45, 45, 90
• 35, 55, 90

Multiple Choice

The sides of an equilateral triangle have...

• different measures.

• equal angles

• equal measures.

• 60°.

Multiple Choice

Find x

• 3
• 4
• 2
• 10

Multiple Choice

What is the length of DF?

• 8

• 4

• 25

• 71

Hint: In an isosceles triangle, the two base angles are congruent. If you need to find the vertex angle, just remember what all three angles should add up to!

Hint: In an isosceles triangle, exactly two sides are congruent!

Hint: Start by solving for y...remember the two base angles are congruent! Then, you can find x using your knowledge of what the three angles of a triangle should add up to!

Multiple Choice

If two sides of a triangle are congruent, then the _________________ opposite those sides are congruent.

• sides
• vertices
• angles
• measures

Multiple Choice

Find x

• 10
• 32
• 116
• 16

Multiple Choice

What is the measure of ∠S?

• 60⁰

• 52⁰

• 45⁰

• 36⁰

Multiple Choice

What is the measure of ∠A?

• 46

• 134

• 90

• 88

Multiple Choice

• A
• B
• C
• D