Question

Решите систему уравнений подстановки {х-у=3,и 2х-3у=-1 решите

Answer 1

$\left \{ {x-y=3} \atop {2x-3y=-1}} \right. \left \{ {{x=3+y} \atop {2(3+y) -3y=-1}} \right. \left \{ {{x=3+y} \atop {6+2y-3y=-1}} \right. \left \{ {{x=3+y} \atop {6 -1y=-1}} \right. \left \{ {{x=3+y} \atop {-1y=-1-6}} \right.$$\left \{ {{x=3+y} \atop {-1y= -7}} \right. \left \{ {{x=3+y} \atop {y=7}} \right. \left \{ {{x=3+7} \atop {y=7}} \right. \left \{ {{x=10} \atop {y=7}} \right.$