For what value(s) of k is the following equation satisfied?

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For what value(s) of k is the following equation satisfied, 2k - 9 - k = 4k + 6 - 3k?

A. -5
B. 0 only
C. 5/2 only
D. No value
E. Any value

The OA is D.

I'm confused with this PS question, but I think that I can get the answer of teh following ways,

First:

I can take each answer option and evaluate the equation and see for which value(s) of k the equation is satisfied, right?

Second:

I can isolate k of the equation and get it value, then

2k - 9 - k = 4k + 6 - 3k
k - 9 = k + 6
-9 = 6

That's mean that the equation is not satisfied for any value(s) of k, right?

Experts, any suggestion? Thanks in advance.

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by Brent@GMATPrepNow » Sun Jan 28, 2018 7:42 am
LUANDATO wrote:For what value(s) of k is the following equation satisfied, 2k - 9 - k = 4k + 6 - 3k?

A. -5
B. 0 only
C. 5/2 only
D. No value
E. Any value

The OA is D.

I'm confused with this PS question, but I think that I can get the answer of teh following ways,

First:

I can take each answer option and evaluate the equation and see for which value(s) of k the equation is satisfied, right?

Second:

I can isolate k of the equation and get it value, then

2k - 9 - k = 4k + 6 - 3k
k - 9 = k + 6
-9 = 6

That's mean that the equation is not satisfied for any value(s) of k, right?

Experts, any suggestion? Thanks in advance.
Your approach is perfect.
Since the k's cancel out, we are left with the nonsensical equation -9 = 6
So, there are NO values of k that will make the left side of the equation equal the right side.

Answer: D

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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by Scott@TargetTestPrep » Sun Jul 28, 2019 8:36 am
BTGmoderatorLU wrote:For what value(s) of k is the following equation satisfied, 2k - 9 - k = 4k + 6 - 3k?

A. -5
B. 0 only
C. 5/2 only
D. No value
E. Any value
Simplifying, we have:

k - 9 = k + 6

We see that there are no values that will allow k - 9 to equal k + 6.

Answer: D

Scott Woodbury-Stewart
Founder and CEO
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