## If $$2x + y = 18$$ and $$3x = 17 + y,$$ what is the value of $$x?$$

##### This topic has expert replies
Legendary Member
Posts: 2898
Joined: 07 Sep 2017
Thanked: 6 times
Followed by:5 members

### If $$2x + y = 18$$ and $$3x = 17 + y,$$ what is the value of $$x?$$

by Vincen » Thu Mar 24, 2022 1:04 pm
If $$2x + y = 18$$ and $$3x = 17 + y,$$ what is the value of $$x?$$

A. 1
B. 4
C. 7
D. 9
E. 13

Source: Veritas Prep

### GMAT/MBA Expert

GMAT Instructor
Posts: 16176
Joined: 08 Dec 2008
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

### Re: If $$2x + y = 18$$ and $$3x = 17 + y,$$ what is the value of $$x?$$

by [email protected] » Fri Mar 25, 2022 6:03 am
Vincen wrote:
Thu Mar 24, 2022 1:04 pm
If $$2x + y = 18$$ and $$3x = 17 + y,$$ what is the value of $$x?$$

A. 1
B. 4
C. 7
D. 9
E. 13

Source: Veritas Prep
Let's use the elimination method...

GIVEN:
2x + y = 18
3x = 17 + y

Take 3x = 17 + y and subtract y from both sides to get: 3x - y = 17

We now have:
2x + y = 18
3x - y = 17

ADD the two equations to get: 5x = 35
Solve: x = 7

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com

• Page 1 of 1