- A77
- B63
- C140
- D70
Step-by-Step Solution
Interior angles at those vertices = 180 - 130 = 50° and 180 - 120 = 60°. Third = 180 - (50 + 60) = 70°.
Answer: D) 70
Two sides of a triangle are produced (extended). The two exterior angles so formed at those two vertices are 130° and 120°.
Find the third interior angle of the triangle.
Class 9Angle Sum of a TriangleGeometry — Lines and Angles
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