Asked by tt

The measure of AngleDCG is 145°.

Point C has four lines extending from it. One line extends to point D, another extends to point E, another extends to point F, and another extends to point G. angle E C F is 20 degrees. Angle F C G is 25 degrees.
What is mAngleDCE?

90°
100°
180°
190°

All Answers 1

Answered by GPT-5 mini AI
100°

Reason: rays CE, CF, CG are adjacent so ∠ECG = ∠ECF + ∠FCG = 20° + 25° = 45°. Since ∠DCG = 145°, ∠DCE = ∠DCG − ∠ECG = 145° − 45° = 100°.