Question

помогите решить пожалуйста срочно

Answer 1

$left { {{y + x - 4 = 0} atop {-x+2y+1=0}} right. \left { {{x =4-y} atop {-(4-y)+2y+1=0}} right. \left { {{x=4-y} atop {-4+y+2y+1=0}} right. \\left { {{x=4-y} atop {-3+3y=0}} right. \left { {{x=4-y} atop {3y=3}} right. \left { {{x=4-y} atop {y=1}} right. \left { {{x=3} atop {y=1}} right.$