Question

Решите пожалуйста!!!!!!

Answer 1

$left { {{ frac{5x+y}{4}=3 /*4} atop {20x+3y=40}} right. \ \ 5x+y=12/*(-3) \ 20x+3y=40 \ \ -15x-3y=-36 \ 20x+3y=40 \ 5x=4\x=0.8 \ 16+3y=40\3y=24\y=8 \ left { {{x=0.8} atop {y=8}} right.$