Isosceles and Equilateral Triangles
10th Grade · Math · 90 min· Savvas Envision Geometry
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Learning Objective
I can apply properties of isosceles and equilateral triangles to determine unknown angle measures and side lengths.
- 1
In an isosceles triangle, the two base angles are congruent, meaning they have the same measure.
- 2
If all three sides of a triangle are congruent, then all three angles are congruent and each angle measures 60 degrees, making it an equilateral triangle.
- 3
If two sides of a triangle are congruent, the angles opposite those sides are congruent, and the sum of all angles in the triangle equals 180 degrees.
