Question 1068453
{{{system(x+y=12,xy=-45)}}}


15 and -3.




Do you want to use algebra for that?
{{{x=12-y}}}
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Substitute.
{{{(12-y)y=-45}}}
{{{12y-y^2+45=0}}}
{{{-y^2+12y+45=0}}}
{{{y^2-12y-45=0}}}
Factorable...
{{{(y+3)(y-15)=0}}}
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