CHECK THE COMPLETE QUESTION AND ITS ATTACHMENT BELOW
circle O, and are diameters. Arc ED measures 17°. Circle O is shown. Line segments F C and A E are diameters. Line segments C O and B O are radii. Point B is between points A and C, and point C is between points E and C. Angle D C is a right angle. What is the measure of Arc E F C? 107° 180° 253° 270°
Answer:
Arc EFC = 253°
Explanation:
From the attachment, we know we are dealing with a circle which has
360 degrees.
If we check that attachment we can deduced that we have
Arc EFC
Arc CD
Arc DE
And everything together give us 360,
Arc EFC + Arc CD + Arc DE = 360
It an established rule that the central angle of an intercepted arc is equal to the measure of the arc, then if we check the figure again,
Arc CD is 90 degrees since the central angle is 90 degrees given
Arc DE is 17 degrees
Arc EFC + Arc CD + Arc DE = 360
If we input all the figures
Arc EFC + 90 + 17 = 360
Arc EFC + 107 = 360
Arc EFC = 360 - 107
Arc EFC = 253
Thefore, Arc EFC = 253°