Answer: Choice C
No solutions if k is anything but 21
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Step-by-step explanation:
Let's multiply everything in the first equation by 3
3x-2y = 7
3*(3x-2y) = 3*7
9x - 6y = 21
We have the 9x-6y match perfectly with the left hand side of the second original equation.
If k = 21, then we have two identical equations that produce infinitely many solutions.
If
, then this system is inconsistent and has no solutions.