177x-543y=897 (2)
( 1)+(2)
500x-86y=2000
x=4+86y/500=4+0. 172y
( 1)-(2)
186x+ 1000y=206
(4+0. 172y)* 186+ 1000y = 206
y =-0.52 132 187 1
x=3.9 10332638