Mathematics Grade 6 15 min

Triangle Angle-Sum Theorem

Triangle Angle-Sum Theorem

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1

A triangle has angles 50° and 70°. What is the third angle?

2

A right triangle has one angle of 40°. Find the missing angle.

3

An isosceles triangle has a top angle of 80°. Find the two base angles.

Sample Practice Questions

Easy
A triangle has angles of 60° and 70°. What is the measure of the third angle?
0.40°
1.50°
2.60°
3.70°
Easy
Two angles in a triangle are 100° and 40°. What is the third angle?
0.40°
1.50°
2.30°
3.60°
Easy
A triangle has angles of 30° and 50°. Find the missing angle.
0.90°
1.110°
2.100°
3.80°

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