(1-10/7)×=2 4/1 (4/1+5/1)×=1 5/4 (3 8/1+1 4/3)×=4/3 (2 12/1-1 6/5)×=4/3
1. x=-56/3 2.x=5/36 3.x=1/19 4.x=10/171