In circle A shown below, m bc is 67° and m ef is 74°:
What is m∠ FDE? (3 points)

37°
74°
70.5°
33.5°

Question

In circle A shown below, m bc is 67° and m ef is 74°:
What is m∠ FDE? (3 points)

    37°
	74°
	70.5°
	33.5°

anonymous · Answer

attachment

anonymous · Answer

i got 74 degrees

jtvatsim · Answer

In this case, the angle won't be 74 degrees, since point D is not in the exact center of the circle.

anonymous · Answer

@music_me @jtvatsim okay can you help me out?

jtvatsim · Answer

The formula you will need is this one: 
The angle formed by two intercepting chords is 1/2 the sum of the intercepted arcs. 

Let's unpack this to see how this actually works. :)

jtvatsim · Answer

The "angle formed by two intercepting chords" in your picture is FDE, that's what we are trying to find.

jtvatsim · Answer

The "intercepted arcs" are BC = 67* and FE = 74*.

jtvatsim · Answer

So, by the formula I gave above we get this:
FDE = 1/2 (67* + 74*) = 1/2 ( 141 ) = 70.5*.

Does that make sense?  :)

anonymous · Answer

it does! thank you for helping me understand it!!

jtvatsim · Answer

No problem! Good luck!