Solve the system :
3x+4y=-3
x+2y=-5
We can solve using the combinations method:
Multiply the second equation by -2, then add the resulting equation to the first equation:
3x+4y=-3
-2x-4y=10
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x=7
Substituting x=7 into the first equation we get:
3(7)+4y=-3
4y=-24
y=-6
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The solution is (7,-6)
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Check: 3(7)+4(-6)=21-24=-3 and 7+2(-6)=7-12=-5
The graphs:
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