If the measure of arc BCD is 220°, what is the measure of angle BCD?

80˚

50°

70°

40°

Question

If the measure of arc BCD is 220°, what is the measure of angle BCD?

80˚

50°

70°

40°

anonymous · Answer

attachment

shubhamsrg · Answer

measure of arc BAD = 360 - measure of BCD = 140
let center be O
now BOD and BCD can be considered to be part of the same segment
thus angle BCD= 1/2 angle BOD (quite common circle theorem)
will this help?

anonymous · Answer

can you walk me thru it please. step by step

shubhamsrg · Answer

hmmn,,|dw:1340035997414:dw|
let O be the center
now we easily see here that angle BOD = 140 degress ( 360-220)
in a circle,,angle at the center is twice than an the circumference..
thus angle BOD = 2(angle BCD)
solve for BCD now..
clearer this time mam?