Answer:
84°
Explanation:
Solve for n. Note that the angle measurements of a circle will equal 360°. Set all the angles = 360°.
7n + 12 + 13n - 16 + 6n = 360
Combine like terms:
(7n + 13n + 6n) + (12 - 16) = 360
26n - 4 = 360
Isolate the variable, n. Note the equal sign, what you do to one side, you do to the other. First, add 4 to both sides:
26n -4 (+4) = 360 (+4)
26n = 360 + 4
26n = 364
Next, divide 26 from both sides:
(26n)/26 = (364)/26
n = 364/26
n = 14
Next, plug in 14 for n in the angle measurement, 6n:
6n = 6(14) = 84°
Note that these are central angles, which means that the arc's will be the same measurement as the angle's measurement.
arcBC = 84°
84° is your answer.
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