6x+2y=-4" (1)" 3x-4y=-10" (2)" "extend the equation (2) by 2" 6x-8y=-20" (3)" "eliminate the equation (3) from (1) side by side" cancel(6x)-cancel(6x)+2y+8y=-4+20 10y=16 y=16/10 y=1,6 "now use (1)" 6(1,6)+2y=-4 9,6+2y=-4 2y=-4-9,6 2y=-13,6 y=-(13,6)/2 y=-6,8