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If m ad=103°, and m bc =115°, what is m< bec?
a. 38°
b. 18°
c. 58°
d. 78°

1 Answer

5 votes

Final answer:

The measure of angle BEC is 38°.

Step-by-step explanation:

To find the measure of angle BEC, we need to subtract the given angles mAD and mBC from 180° since BEC is a straight angle.

mBEC = 180° - mAD - mBC

Substituting the given values: mBEC = 180° - 103° - 115° = -38°.

Since angles cannot be negative, we take the positive value of -38° which is 38°.

Therefore, the measure of angle BEC is 38° (option a).

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