Question

question 10 of 10
what is the measure of \\(\overline{def}\\)?

Explanation:

Step1: Relate inscribed angle to arc

Inscribed angle ∠DEF = 78° intercepts arc DF. By theorem: ∠ = ½ arc DF.

Step2: Calculate arc DF

arc DF = 2×78° = 156°.

Step3: Find major arc DEF

Total circle = 360°, so arc DEF = 360° - 156° = 204°.

Answer:

D. 204°