1) 2/3+x=1
x=1-2/3
x=3/3-2/3
x=1/3
2) 4/5+x=1/2
x=1/2-4/5
x=5/10-8/10
x= -3/10
3) 7/20+x=1/3
x=1/3-7/20
x=20/60-21/60
x= -1/60
4)-5/16+x=17/18
x= 17/18+5/16
x= 136/144+45/144
x= 181/144
x= 1 37/144
5) x-17/18=-10/9
x= -10/9+17/18
x= -20/18+17/18
x = -3/18
x= -1/6
6) 2/5-x=1/3
-x = 1/3-2/5
-x = 5/15 - 6/15
-x= -1/15
x= 1/15
7) -8/9-x=17/18
-x = 17/18+8/9
-x= 17/18+16/18
-x = 33/18
x= -1 15/18
x = -1 5/6
8) -7/9-x=13/18
-x = 13/18+7/9
-x = 13/18+14/18
-x= 27/18
-x = 1 9/18
-x= 1 1/2
x= -1 1/2