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Sub 505 (Easy)|   Algebra|      
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Bunuel
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 13 May 2018, 21:23
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C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

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5% (low)

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91% (00:38) correct 9% (01:06) wrong based on 140 sessions

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

A. 1
B. 4
C. 7
D. 9
E. 13
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C
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 13 May 2018, 21:27
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IMO C

1st eqn: 2*x + y = 18
2nd eqn; 3*x - y = 17
Adding both: 5*x = 35 or x = 7
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 30 Jun 2018, 06:30
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If 2x+y=18 and 3x=17+y, what is the value of x?
A. 1
B. 4
C. 7
D. 9
E. 13
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generis
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 30 Jun 2018, 06:39
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globaldesi
If 2x+y=18 and 3x=17+y, what is the value of x?
A. 1
B. 4
C. 7
D. 9
E. 13
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Rewrite \(3x=17+y\), then add the equations

\(3x-y=17\) and
\(2x+y=18\)
-----------------------
\(5x=35\)
\(x=7\)

Answer C
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 30 Jun 2018, 06:40
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globaldesi
If 2x+y=18 and 3x=17+y, what is the value of x?
A. 1
B. 4
C. 7
D. 9
E. 13
Show more

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

Answer: C

Cheers,
Brent
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 30 Jun 2018, 10:13
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globaldesi
If 2x+y=18 and 3x=17+y, what is the value of x?
A. 1
B. 4
C. 7
D. 9
E. 13
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Merging topics. Please check the discussion above.
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 04 Jul 2018, 19:28
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Bunuel
If 2x + y = 18 and 3x = 17 + y, what is the value of x?

A. 1
B. 4
C. 7
D. 9
E. 13
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Manipulating the second equation, we have:

3x - y = 17

Adding the equations, we have:

2x + y = 18
+ 3x - y = 17

5x = 35

x = 7

Answer: C
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 05 Jul 2018, 08:52
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Bunuel
If 2x + y = 18 and 3x = 17 + y, what is the value of x?

A. 1
B. 4
C. 7
D. 9
E. 13
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\(6x = 54 - 3y\)------------------------(I)
\(6x = 34 + 2y\)-------------------------(II)

Or, \(54 - 3y = 34 + 2y\)

Or, \(5y = 20\)

So, \(y = 4\)

Hence \(x = \frac{34 + 8}{6}\)

Or, x = 7 , Answer must be (C)
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 14 Jul 2018, 19:19
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Bunuel
If 2x + y = 18 and 3x = 17 + y, what is the value of x?

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

We have:

2x + y = 18

and

3x - y = 17

Adding the equations together, we see that the y terms cancel, and thus we have:

5x = 35

x = 7

Answer: C
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If 2x + y = 18 and 3x = 17 + y, what is the value of x? 15 Jul 2018, 02:25
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OA: C
2x + y = 18 ......(1)
3x = 17 + y.......(2)

As 2x and 18 are even, this imply that y will be even.
We have to find value of x , but there is high probability that value of y would be one of wrong option.
only option B is even, so assuming the value of y =4, we can check whether (1) and (2) gives the same value of x.
Both equation are giving x= 7, when we put y=4 so our assumption was correct.
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