Kite DCFE is inscribed in circle A shown below. If the measure of DEF is 266°, what is the measure of ∡DEF?
Wait, you're wanting to know the angle of DEF?
∡DEF is 266
i don't understand. given DEF and you wanna measure of ∡DEF?
The arch of DEF is 266
As far as I can tell, this question is saying "x is 5. What is x?"...
There are 360 degrees in a circle. If the great arc is 266, the rest of the circle is 360 - 266 = 94. Then, angle DEF is an inscribed angle intersecting that 94 degree arc, so it is then half of it. Answer is 94/2 = 47
If arc DEF = 266 then arc DCF = 94 Join DA and FA then angle DAF = 94..... angle standing on the arc DCF then angle DEF = 47 angle at the centre is double the angle at the circumference standing on the same arc
Could have also done inscribed angle with ∡DCF to get it = to 133 and then opp angles of inscribed quad supp to find ∡DEC = 47
yep... DCF = 133 angle at the centre is double the angle at the circumference DCFE is a cyclic quadrilateral (opposite angles spplementary then DEF = 47
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