bekarys200003 4,2-1,4x-0,9x-1,8=4,7
2,4-2,3x=4,7
-2,3x=2,3
x=-2,3/2,3
x=-1

Oneginka 4.2-1.4x-0.9x-1.8=4.7
-1.4x-0.9x=4.7-4.2+1.8
-2.3x=2.3
x=-(2.3\2.3)
x=-1