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16 Sep 2014, 01:03



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03 Mar 2015, 05:44
I think this question is good and helpful.
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16 Aug 2016, 05:48
I think this is a highquality question and I agree with explanation.



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11 Sep 2016, 02:25
Bunuel wrote: Official Solution:In rectangle \(ABCD\), \(E\) is the point of intersection of diagonals. If angle \(ABD\) is twice angle \(EAD\), what is the value of angle \(CED\)? A. 30 degrees B. 45 degrees C. 60 degrees D. 90 degrees E. 120 degrees Look at the diagram below: Notice that since \(\angle{BAD}=90\) degrees then \(\angle{EAB}=90x\) degrees. Next, since diagonals of a rectangle are equal and bisect each other then \(AE=BE\). So, \(\angle{EAB}=\angle{EBA}\): \(90x=2x\), which gives \(x=30\). Thus, \(\angle{EAB}=\angle{EBA}=60\) and \(\angle {AEB}=60\) degrees. Finally as \(\angle{AEB}=\angle{CED}\) then \(\angle{CED}=60\) degrees. Answer: C Hi, Aren't the diagonals of a rectangle an angular bisector ? AS, WE KNOW THAT DE = BE. So, angle a should have each angle = 45 degree ? angle DAE = angle BAE = 45 ? thanks



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11 Sep 2016, 03:02
19941010 wrote: Bunuel wrote: Official Solution:In rectangle \(ABCD\), \(E\) is the point of intersection of diagonals. If angle \(ABD\) is twice angle \(EAD\), what is the value of angle \(CED\)? A. 30 degrees B. 45 degrees C. 60 degrees D. 90 degrees E. 120 degrees Look at the diagram below: Notice that since \(\angle{BAD}=90\) degrees then \(\angle{EAB}=90x\) degrees. Next, since diagonals of a rectangle are equal and bisect each other then \(AE=BE\). So, \(\angle{EAB}=\angle{EBA}\): \(90x=2x\), which gives \(x=30\). Thus, \(\angle{EAB}=\angle{EBA}=60\) and \(\angle {AEB}=60\) degrees. Finally as \(\angle{AEB}=\angle{CED}\) then \(\angle{CED}=60\) degrees. Answer: C Hi, Aren't the diagonals of a rectangle an angular bisector ? AS, WE KNOW THAT DE = BE. So, angle a should have each angle = 45 degree ? angle DAE = angle BAE = 45 ? thanks The diagonal of a rectangle is a bisector only if the rectangle is a square.
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26 Sep 2016, 07:33
Aren't the diagonals of rectangle perpendicular bisector of each other?



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26 Sep 2016, 07:39



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12 Dec 2016, 17:04
I think this is a poorquality question and the explanation isn't clear enough, please elaborate. Hi, can you explain more? Basically, total 3 angles of a triangle is 180. If <AEB = 60, total value of 3 angles in triangle AEB is 150 degree (Because <AEB = 60, <ABE= 60, and <BAE = 30). Moreover, 4 angles AEB + BEC + CED + DEA = 360. As a result, <AEB must be at least 90 degree. Please explain. Thank you so much!



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13 Dec 2016, 02:01
hnguyen26 wrote: I think this is a poorquality question and the explanation isn't clear enough, please elaborate. Hi, can you explain more? Basically, total 3 angles of a triangle is 180. If <AEB = 60, total value of 3 angles in triangle AEB is 150 degree (Because <AEB = 60, <ABE= 60, and <BAE = 30). Moreover, 4 angles AEB + BEC + CED + DEA = 360. As a result, <AEB must be at least 90 degree. Please explain. Thank you so much! The question is fine. You just made mistake in calculations. The measure of angle BAE is 60, not 30. Please reread the discussion more above carefully this time.
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21 Jun 2017, 07:41
The answer is option C. Well explained above.
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22 Aug 2017, 14:46
I think this is a highquality question and I agree with explanation.



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04 Nov 2017, 02:22
Can you please explain the angle measure 2x for EBA



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