Answer:
m∠BFE = 171º
BE = 219º
Step-by-step explanation:
∠BFE is supplementary to ∠EFC
m∠BFE = 180 - 9
m∠BFE = 171º
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The angle between two chords is equal to half the sum of the intercepted arcs:
∠BFE = (DC + BE)2
171 = (123 + BE)/2
342 = 123 + BE
219º = BE
