MISTAKE in Gruber's Complete Math Workbook?!

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1

<p>I'm currently working through a test in Gruber's math workbook, and it looks like one of his questions may have two answers (Correct my observation if needed because my math might be wrong):</p>

<p>Here's the question:</p>

<p>For which value of k will the system of the equations below have no solution?</p>

<p>1) 4x-3y=9
2) 8x-ky=19</p>

<p>A) +6, B) +3, C) 0, D) -3, E) -6</p>

<p>The answer key says that the only possible answer is E, but wouldn't +6 work too? Because if you double equation 1 and make k +6, the same equations will equal different solutions (18 and 19), so wouldn't that count as the right answer, as well?</p>

2

<p>If the problem is as you have written it, then A and not E would be the answer. But are you sure you have transcribed it correctly?</p>

3

<p>Those companies seldom make mistakes. just ignore it and move on</p>

4

<p>I agree with pckeller. </p>

<p>IF you have reproduced the question correctly, then the only correct answer is A, k = 6. On the other hand, if (as one possible example) equation 2 is really -8x - ky = 19, then the only correct answer is E, k = -6.</p>

<p>But in no event are there two correct answers.</p>