$d)\left \{ {{8x+2y=10} \atop {3x-y=2}} \right.⇔\left \{ {{8x+2y=10} \atop {6x-2y=4}} \right.$
$⇔\left \{ {{14x=14} \atop {3x-y=2}} \right.⇔\left \{ {{x=1} \atop {3.1-y=2}} \right.$
$⇔\left \{ {{x=1} \atop {y=1}} \right.$
$e)\left \{ {{x+5y=-4} \atop {x-y=2}} \right.⇔\left \{ {{6y=-6} \atop {x-y=2}} \right.$
$⇔\left \{ {{y=-1} \atop {x-(-1)=2}} \right.⇔\left \{ {{y=-1} \atop {x+1=2}} \right.$
$⇔\left \{ {{y=-1} \atop {x=1}} \right.$
$g)\left \{ {{x+3y=4} \atop {2x+y=3}} \right.⇔\left \{ {{x+3y=4} \atop {-6x-3y=-9}} \right.$
$⇔\left \{ {{-5x=-5} \atop {2x+y=3}} \right.⇔\left \{ {{x=1} \atop {2.1+y=3}} \right.$
$⇔\left \{ {{x=1} \atop {y=1}} \right.$
#CHÚC BẠN HỌC TỐT
#10/1/2021
