in this problem, you can take advantage of the property of elimination
subtract the bottom equation from the top equation
x+6y=15
- -x+4.=5
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0x+2y=10
you then divide both sides by 2
y=5
now that you know what y equals, plug it into one of the equations and solve for x.
x+6(5)=15
x+30=15
subtract 30 from both sides
x=-15
the final answer is x= -15 y = 5 aka the coordinate (-15,5)