- A60
- B120
- C54
- D66
Step-by-Step Solution
The angles of a triangle add to 180°, so the third angle = 180° − (55° + 65°) = 180° − 120° = 60°.
Answer: A) 60
In a triangle, two of the angles measure 55° and 65°. The third angle is (in degrees):
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