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In the figure above, if m and n are parallel, then x=?

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by AAPL » Tue Nov 07, 2017 1:46 pm
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In the figure above, if m and n are parallel, then x=?

(A) 30
(B) 50
(C) 70
(D) 105
(E) 210

The OA is C.

Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer.

Because m is parallel to n we know that x = 2x -30

Now we just solve for x and we get x = 30.

Answer should be A, right? Thanks.
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by Brent@GMATPrepNow » Tue Nov 07, 2017 1:49 pm
AAPL wrote:Image
In the figure above, if m and n are parallel, then x=?

(A) 30
(B) 50
(C) 70
(D) 105
(E) 210

The OA is C.

Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer.

Because m is parallel to n we know that x = 2x -30

Now we just solve for x and we get x = 30.

Answer should be A, right? Thanks.
You are correct; the answer SHOULD be A (since we know that x = 2x - 30, and the solution is x = 30)

What's the source of this question?

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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by EconomistGMATTutor » Tue Nov 07, 2017 2:16 pm
AAPL wrote:Image
In the figure above, if m and n are parallel, then x=?

(A) 30
(B) 50
(C) 70
(D) 105
(E) 210

The OA is C.

Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer.

Because m is parallel to n we know that x = 2x -30

Now we just solve for x and we get x = 30.

Answer should be A, right? Thanks.
Hi AAPL,
Let's take a look at your question.

Lines m and n are parallel. The angles x and (2x - 30) are called corresponding angles.
When two parallel lines are cut by another line then the corresponding angles formed are always congruent.

Therefore,
x = 2x - 30
2x - x = 30
x = 30

Therefore, Option A is correct.

Hope its helps.
I am available if you'd like any follow up.
GMAT Prep From The Economist
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Our average student improves 98 points.

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by EconomistGMATTutor » Tue Nov 07, 2017 2:16 pm
AAPL wrote:Image
In the figure above, if m and n are parallel, then x=?

(A) 30
(B) 50
(C) 70
(D) 105
(E) 210

The OA is C.

Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer.

Because m is parallel to n we know that x = 2x -30

Now we just solve for x and we get x = 30.

Answer should be A, right? Thanks.
Hi AAPL,
Let's take a look at your question.

Lines m and n are parallel. The angles x and (2x - 30) are called corresponding angles.
When two parallel lines are cut by another line then the corresponding angles formed are always congruent.

Therefore,
x = 2x - 30
2x - x = 30
x = 30

Therefore, Option A is correct.

Hope its helps.
I am available if you'd like any follow up.
GMAT Prep From The Economist
We offer 70+ point score improvement money back guarantee.
Our average student improves 98 points.

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