Х-7,21=-8 1/20
х-7 21/100=-8 1/20
х=-8 1/20+7 21/100
х=-8 5/100+7 21/100
х=-805/100+721/100
х=-84/100
х=-21/25
х=-0,84
m-1 3/4=-3,7
m-1 3/4=-3 7/10
m=1 3/4-3 7/10
m=1 15/20-3 14/20
m=35/20-74/20
m=-39/20
m=-1 19/20
m=-1,95
у-2=-4 1/3
у=-4 1/3+2
у=-13/3+6/3
у=-7/3
у=-2 1/3