3-2-29
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When doing this problem, we need to get the leading coefficients
to be the same, so we might start by multiplying that top
equation through by -5, so we get -5 X -15 Y equaling -15.
If I add it exactly the way it is with the second equation,
because they're currently additive inverses, the five XS
are going to cancel and we get -13 Y equaling -26.
If we divide each side by a -13, we get Y equal 2.
If we go back to the original and we multiply the top one by
two, so we'd get 2X plus 6Y equaling 6, and we multiply the
bottom one through by a -3.
What that does is it gives us additive inverses on the Y term,
so -15 X -6 Y equal 33.
So when we add those directly, we get -13 X the +6 Y -6 Y
cancel equaling 39.
If we divide each by -13, we get X equal -3.
So the solution set as -3 two.
It's consistent and in dependent.