Решите систему 2x+3y=82.8 x+2y=56.9

{2x+3y=82.8

{x+2y=56.9

{x=56.9-2y

{  113.8-y=82.8

{y=113.8-82.8

{y=31

{x= -5.1 

2x+3y=82.8

x+2y=56.9

x+2y=56.9

y=-x/2+28.45

2x+3y=82.8

2x+3*(-x/2+28.45)=82.8

2x-1.5x+85.35-82.8=0

0.5x+2.55=0

x=-2.55/0.5

x=-5.1

x+2y=56.9

-5.1+2y=56.9

y=62/2

y=31