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If the system of linear equations above has o solution, and a is a constant, then what is the value of a ? |
Answer» <html><body><p>`-2`<br/>`-1/2`<br/>`2`<br/>6</p>Solution :Graphically, a system of linear equations that has no solution <a href="https://interviewquestions.tuteehub.com/tag/indicates-1041501" style="font-weight:bold;" target="_blank" title="Click to know more about INDICATES">INDICATES</a> two parallel lines-that is, two lines that have the same slope but different y-intercepts. To have the same slope, the x-and y-coefficient must be the same. To get from `-2/3` to `-8,` you multiply by 12, so multiply `-1/2x ` by 12 as well to yield 6x. Because the other x-coeffieient is a, it must be that `a =6,` and (D) is correct. Note that, even though it is more work, you could <a href="https://interviewquestions.tuteehub.com/tag/also-373387" style="font-weight:bold;" target="_blank" title="Click to know more about ALSO">ALSO</a> write each <a href="https://interviewquestions.tuteehub.com/tag/equation-974081" style="font-weight:bold;" target="_blank" title="Click to know more about EQUATION">EQUATION</a> in slope-intercept <a href="https://interviewquestions.tuteehub.com/tag/form-996208" style="font-weight:bold;" target="_blank" title="Click to know more about FORM">FORM</a> and <a href="https://interviewquestions.tuteehub.com/tag/set-11758" style="font-weight:bold;" target="_blank" title="Click to know more about SET">SET</a> the slopes equal to each other to solve for a.</body></html> | |