请采纳
x减三分之一加五分之二等于九分之五
x- 1/3 +2/5 = 5/9
x + 1/15 =5/9
x = 22/45
通分
X-1/3+2/5=5/9
通分后为,X-15/45+18/45=25/45
左边两项移到右边,X=25/45+15/45-18/45=22/45
x-1/3+2/5=5/9
x=5/9+1/3-2/5=25/45+15/45-18/45=22/45
x-1/3+2/5=5/9
x=1/3-2/5+5/9
x=22/45