No, in order for the lines to be parallel, the slopes have to be the same, it does not matter what the slopes are as long as they are the same slope. The lines could still be parallel if the slopes are negative.
1/4= 3/12 so it would be 5/12-3/12= 2/12
2/12= 1/6
K^2-5k-50
(k-10)(k+5)
This is because k*k=k^2 (your first term), 5k-10k=-5k (your second term) and -10*5=-50 (your last term).
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