Respuesta :

I'll solve it algebraically


x+y=4
x-3y=12

multiply first equatoin by -1 and add to second

-x-y=-4
x-3y=12 +
0x-4y=8


-4y=8
divide both sides by -4
y=-2

sub back

x+y=4
x+-2=4
add 2 to both sides
x=6

x=6
y=-2
(6,-2)
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