А)2×-3/3+7×-13/6+5-2×/2=×-1
2 (2×-3)+7×-13+3 (5-2×)/6=×-1
4×-6+7×-13+15-6×/6=×-1
5×-4/6=×-1 |*6
5×-4=6 (×-1)
5×-4=6×-6
-×=-2 |* (-1)
×=2
б)×-2/5+2×-5/4+4×-1/20=4-×
4 (×-2)+5 (2×-5)+4×-1/20=4-×
4×-8+10×-25+4×-1/20=4-×
18×-34/20=4-× |*20
18×-34=80-20×
18×+20×=80+34
38×=114
×=3
в) 5×-4/3+3×-2/6+2×-1/2=3×-2
2 (5×-4)+3×-2+3 (2×-1)/6=3×-2 |*6
10×-8+3×-2+6×-3=6 (3×-2)
10×+3×+6×-18×=8+2+3-12
×=1
г) 3-5×/5+3×-5/3+6×+7/15=2×+1
3 (3-5×)+5 (3×-5)+6×+7/15=2×+1 |*15
9-15×+15×-25+6×+7=15 (2×+1)
6×-30×=15-9+25-7
-24×=24
×=-1