Interior Angles of Triangles
9th Grade · Math · 45 min
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Learning Objective
I can prove that the sum of the interior angles of a triangle is 180 degrees.
- 1
The Triangle Sum Theorem states that the sum of the three interior angles of any triangle will always add up to 180 degrees.
- 2
If a triangle has angles A, B, and C, then the equation A + B + C = 180 can be used to solve for missing angle measurements.
- 3
When solving for a variable within angle expressions, remember to combine like terms before isolating the variable using inverse operations.
