In the diagram above, what is the measure of angle y? (1) x = 30° (2)

Question

https://gmatclub.com/forum/download/file.php?id=60716 In the diagram above, what is the measure of angle y? (1) x = 30° (2) line AB is parallel to line CD anplotg_img1.png

Bunuel · Accepted Answer

MAGOOSH OFFICIAL SOLUTION:

First of all, notice from the diagram: if the lines are parallel, then the two angles would be equal, x = y; but, if the lines are not parallel, we can conclude absolutely nothing about x & y. Furthermore, a visual assessment is not enough — yes, the lines look parallel, but that’s not a guarantee that they are parallel, and without this guarantee, we can do nothing.

Statement #1: Here, we know angle x, but we don’t know whether the lines are parallel, so we can conclude nothing. Alone & by itself, this statement is insufficient.

Statement #2: Now, we know the lines are parallel, but we don’t know the values of any variables. Alone & by itself, this statement is insufficient.

Combined Statements: Now, we know the lines are parallel, and we know x = 30°, so this means y = 30°. We now have definitive information that allows us to answer the prompt question. Together, the statements are sufficient.

Answer = C

CrackverbalGMAT · Answer

From Statement 1:   x = 30 does not tell us about y, as we do not know if the 2 lines are parallel.

Therefore statement 1 Alone is insufficient. Answer Options could be B, C or E.

From Statement 2:   AB is parallel to CD, lets us know that x = y, but we do not have the value of x.

Therefore statement 2 Alone is insufficient. Answer Options could be C or E.

Combining both statements  , gives us that AB is // to CD and that x = 30. Therefore y = 30 as these are alternate angles.

Option C

Arun Kumar

In the diagram above, what is the measure of angle y? (1) x = 30° (2)

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GMAT Data Sufficiency (DS) Questions

In the diagram above, what is the measure of angle y? (1) x = 30° (2)

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