we have the 2 equations
1- ) 5x-8y=6
2-) -6x-3y=18
multiplying the first equation by 3 and the second equation by 8 then subtracting
1-) 15x-24y=18
2-) -48x-24y=144
-48x-24y=144
(-) 15x-24y=18
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-63x = 126
x=-2
substituting in equation 1
5(-2)-8y=6
-10-8y=6
-8y=16
y=-2
the soultion is (-2,-2)