If x + y = 5y - 13 and x - y = 5, then x =

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BTGModeratorVI wrote:
Mon Sep 07, 2020 7:01 am
If x + y = 5y - 13 and x - y = 5, then x =

A. 11
B. 12
C. 13
D. 14
E. 15

Answer: A
Source: Kaplan
GIVEN:
x + y = 5y − 13
x − y = 5

Rearrange the terms in the top equation to get:
x - 4y = -13
x − y = 5

Take the bottom equation and multiply both sides by 4 to get:
x - 4y = -13
4x - 4y = 20

Now subtract the bottom equation from the top equation to get: -3x = -33
Divide both sides by -3 to get x = 11

Answer: A

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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