paper test geometry question

This topic has expert replies
Source: — Problem Solving |

User avatar
Legendary Member
Posts: 543
Joined: Fri Jan 18, 2008 1:01 am
Thanked: 43 times
GMAT Score:580

by codesnooker » Sun Oct 05, 2008 10:48 am
It is very simple problem based on parallelism and isosceles triangle property concept.

Given things:

i) AB || CE
ii) angle (y) = 45 degree.
iii) CE = ED

Also, angle (y) + angle (ECD) + angle (CDE) = 180 degree.

Now as CE = ED, therefore angle (ECD) = angle (CDE), by the property of isosceles triangle.

Therefore, angle (ECD) = (180 - 45)/2 = 67.5 degree.

Now as AB || CE, therefore by parallel lines properties, angle (x) = 67.5

Master | Next Rank: 500 Posts
Posts: 118
Joined: Fri Apr 18, 2008 4:58 am
Thanked: 1 times

by ifthyder » Tue Oct 07, 2008 8:11 am
thanks
Attachments
geometry parallel lines interior angles.JPG