\left \{ {{-2x+6y=9} \atop {-8y=-8 \ => y=1}} \right. -2x+6*1=9 \\ -2x=9-6 \\ -2x=3 \\ x=-1,5 \\ (-1,5;1)" alt=" \left \{ {{6x+3=8x-6y+12} \atop {4x-6y-4x=2y-8}} \right. => \left \{ {{-2x+6y=9} \atop {-8y=-8 \ => y=1}} \right. -2x+6*1=9 \\ -2x=9-6 \\ -2x=3 \\ x=-1,5 \\ (-1,5;1)" align="absmiddle" class="latex-formula">
\left \{ {{ 6(3x+2y)+5(x-3y)=90} \atop {2x+7y+43=0}} \right. => \\
\left \{ {{ 18x+12y+5x-15y=90} \atop {2x+7y+43=0}} \right. =>\left \{ {{ 23x-3y=90|*7} \atop {2x+7y=-43|*3}} \right. => \\
+\left \{ {{ 161x-21y=630} \atop {6x+21y=-129}} \right. 167x=501=>x=3 \\ 2*3+7y=-43 \\ 7y=-43-6 \\ 7y=-49 \\ y=-7 \\ (3;-7)" alt=" \left \{ {{ \frac{3x+2y}{5} + \frac{x-3y}{6} =3|*30} \atop {2x+7y+43=0}} \right. => \left \{ {{ 6(3x+2y)+5(x-3y)=90} \atop {2x+7y+43=0}} \right. => \\
\left \{ {{ 18x+12y+5x-15y=90} \atop {2x+7y+43=0}} \right. =>\left \{ {{ 23x-3y=90|*7} \atop {2x+7y=-43|*3}} \right. => \\
+\left \{ {{ 161x-21y=630} \atop {6x+21y=-129}} \right. 167x=501=>x=3 \\ 2*3+7y=-43 \\ 7y=-43-6 \\ 7y=-49 \\ y=-7 \\ (3;-7)" align="absmiddle" class="latex-formula">