Ask your own question, for FREE!
Mathematics 14 Online
OpenStudy (anonymous):

Is my answer correct? Someone check please :D I got either 40 for the question attached below. Am I correct? Another answer I got was 190 when I switched them around.

OpenStudy (anonymous):

OpenStudy (alexandervonhumboldt2):

x=1/2(140+90)

OpenStudy (alexandervonhumboldt2):

x=185

OpenStudy (alexandervonhumboldt2):

i dont remember the name of the theorem that sates that

OpenStudy (alexandervonhumboldt2):

@opern1112

jimthompson5910 (jim_thompson5910):

I don't know the name either, but it's theorem 4 on this page http://www.regentsprep.org/regents/math/geometry/gp15/circleangles.htm

OpenStudy (anonymous):

I solved it like 140=1/2(x+90) and 90=1/2(x+140)....

jimthompson5910 (jim_thompson5910):

it's actually \[\Large x = \frac{1}{2}(140+90)\] as AlexandervonHumboldt2 stated and as the link states

OpenStudy (anonymous):

How did Alexander get x=185?? I got x=115 if solved in the way mentioned.

OpenStudy (alexandervonhumboldt2):

maybe i mistaked

OpenStudy (alexandervonhumboldt2):

yeah 115

OpenStudy (anonymous):

What if AD was 78 and BC was 116? It says the correct answer is 154 degrees for this question.

jimthompson5910 (jim_thompson5910):

Then you'll have \[\Large x = \frac{1}{2}(78+116)\]

jimthompson5910 (jim_thompson5910):

and yeah, \[\Large x = \frac{1}{2}(140^{\circ}+90^{\circ}) = 115^{\circ}\]

OpenStudy (anonymous):

But the correct answer is 154... The x is on the outside of the circle near BC, unlike the first question where x is inside the circle near the center of arc BC

OpenStudy (anonymous):

Wouldn't 1/2(78+116) give 97? The correct answer is 154. The response feedback was that they solved it by 116=1/2(x+78)

jimthompson5910 (jim_thompson5910):

oh they moved that x to a different spot

jimthompson5910 (jim_thompson5910):

I thought x stayed at the intersection of the two secants

OpenStudy (anonymous):

Is there a difference with x staying in the inside and outside of the circle??

jimthompson5910 (jim_thompson5910):

so yeah, it's \[\Large 116 = \frac{1}{2}(x+78)\] assuming the arc measures are x and 78

jimthompson5910 (jim_thompson5910):

|dw:1419127689683:dw|

jimthompson5910 (jim_thompson5910):

the stuff inside the parenthesis are the arc measures |dw:1419127718090:dw|

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!