how do i solve such questions ???
For what values of 'k' will the pair of equations 3x + 4y = 12 and kx + 12y = 30 not have a unique solution?
12
9
3
7.5
2.5
The correct choice is (B) and the correct answer is 9.
plz help
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- cans
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generally 2 lines either intersect at a point, or they don't intersect at all (when they are parallel)
Thus: to not have a unique solution, lines should be parallel.
slope of 1st = -3/4 = slope of 2nd = -k/12
3/4 = k/12 or k=9
IMO B
Thus: to not have a unique solution, lines should be parallel.
slope of 1st = -3/4 = slope of 2nd = -k/12
3/4 = k/12 or k=9
IMO B
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Scan the answers for a likely candidate.rmazzawi wrote:how do i solve such questions ???
For what values of 'k' will the pair of equations 3x + 4y = 12 and kx + 12y = 30 not have a unique solution?
12
9
3
7.5
2.5
The correct choice is (B) and the correct answer is 9.
If k=9, the second equation becomes 9x+12y=30, which is the same as 3x+4y=10.
This equation contradicts the first equation: 3x+4y=12.
The correct answer is B.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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