In the figure above, which of the following must equal 180?

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My confusion is given in the next post
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by AsadAbu » Mon Aug 29, 2016 7:05 am
In this question, there is no specific indication that 1) THE LINEs are straight lines and 2) all the LINEs go in a ONE particular POINT.
So, without these two important information HOW can we know that the opposite angles (e.g., angle b and angle e) are equal to each other?

From the figure, I know that b+a+g+h=180
Statement ii: Here, I've to prove that b+e+g+h=180 or not. If I can proof that angle 'a' and angle 'e' both are equal to each other then I can say surely b+e+g+h=180. In apparently it seems that angle 'a' and angle 'e' both are equal to each other but we've no information about...
1) THE LINEs are straight lines or not,
2) all the LINEs go in a particular POINT or not

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by [email protected] » Mon Aug 29, 2016 9:09 am
Hi iMyself,

In PS questions, you are meant to 'trust' the picture (meaning that lines that 'look straight' are straight, the picture is drawn to scale, etc.); the exception is when the phrase "figure not drawn to scale" (or equivalent) is written under the picture. In addition, since each of the answers includes at least one of the Roman Numerals, there HAS to be a way to make a deduction about the angles involved in the picture. This is all meant to say that the lines are straight and they all intersect in one spot.

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by Brent@GMATPrepNow » Mon Aug 29, 2016 10:58 am
Here's a video on what can and cannot be assumed when dealing with GMAT diagrams: https://www.gmatprepnow.com/module/gmat ... /video/863

Cheers,
Brent
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