10.153
1) x+3/8=1/2;
x=1/2-3/8;
X=4-3/8;
x=1/8.
2)x-1/4=3/7;
x=3/7+1/4;
x=12+7/28;
x=19/28.
3) 1/7*x*1/3=2;
x/21=2;
x=42.
4) 1/2*x+1/3*x=5/6;
x/2+x/3=5/6;
3x+2x/6=5/6;
5x/6=5/6;
x=1.
5) (1/3)^2+x=(1/2)^2*2;
1/9+x=2/4;
x=1/4-1/9;
x=7/18.
6) 1/2-3/4*(x-3/10)=3/8;
1/2-3/4x+9/40=3/8;
-3/4x=3/8-1/2-9/40;
-3/4x=-14/40;
-3x*40=-14*4;
120x=56;
15x=7;
X=7/15.
10.152
1)1/5a+3/5a+2/7-2/5a=7a+21a+10-14a=30=14a+10
2) общий знаменатель не смогла найти