|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
08 Dec 2015, 15:48
Kudos
Bookmarks
BrainLab
Dear BrainLab,
I'm happy to respond.
We can figure out everything we need about proportional sides by keeping track of the angles. Here's what I mean. 1) Look at the big triangle, ABC. Right angle at B. Say that the angle BAD has a measure of A and the angle DCE has a measure of C. We know that A and C are complementary angles, that is, A + C = 90 degrees. It appears that A > C, which means that BC > AB. Let's assume that is the relationship of these two angles.
2) Look at triangle ABD. Right angle at C. The angle at vertex A still has a measure of A, so the angle at vertex B, angle ABD, just have a measure of C. Again, A > C, so (angle BAD) > (angle ABD), which means that BD > AD.
3) Look at triangle DEC. Right angle at C. The angle at vertex C still has a measure of C, so the angle at vertex D, angle EDC, just have a measure of A. Again, A > C, so (angle EDC) > (angle ECD), which means that EC > DE.
4) Now, look at triangle BED. Right angle at E.
angle (BDE) = 90 - (angle EDC) = 90 - A = C
angle (DBE) = 90 - (angle ABD) = 90 - C = A
Again, A > C, so (angle DBE) > (angle BDE), which means that ED > BE.
Here is a highly accurate diagram of the situation, with the angles color-coded so you can see which angle equals which.
Attachment:
triangle with colored angles.JPG [ 17.12 KiB | Viewed 4901 times ]
Does all this make sense?
Mike
18 Jul 2016, 03:17
Kudos
Bookmarks
I disagree with this question.
It should be clearly stated that the line BD goes from the base to the vertex B. We can't simply trust the image and assume that the line goes straight to B. What if it is slightly on the left\right?
I think that the answer should be E, although I understand the "intention" of the question is to be D.
It should be clearly stated that the line BD goes from the base to the vertex B. We can't simply trust the image and assume that the line goes straight to B. What if it is slightly on the left\right?
I think that the answer should be E, although I understand the "intention" of the question is to be D.
18 Jul 2016, 08:02
Kudos
Bookmarks
iliavko
Dear iliavko,
I'm happy to respond.
My friend, there are a few things that we always can assume on GMAT diagram. One is that if a line segment appears to connect to a point, it actually does connect to that point. You yourself referred to that segment as BD: we don't even have a way of talking about it except to refer to its endpoints, so it would be duplicitous for the GMAT to allow for the segment to have an endpoint something other then the obvious endpoint. If any segment looks like it goes to a point, you can assume that it is God-given truth that the segment in fact does go to that point.
Does all this make sense?
Mike
