Two angles of a triangle measure 39.5°

Question

and 61.7°
. Use the Triangle Angle Sum Theorem to find the measure of the third angle; do not round the answer.(1 point)
Responses

78°
78 degrees

78.8°
78.8 degrees

79°
79 degrees

68.8°

Answer 1

The correct answer is 78.8°.

Since the sum of all three angles in a triangle is always 180°, you can find the measure of the third angle by subtracting the sum of the two given angles from 180°.

180° - (39.5° + 61.7°) = 78.8°

Therefore, the measure of the third angle is 78.8°.