I 2-x I =3
2-х=3
х=2-3
х1=-1
2-х=-3
х=2+3
х2=5
1) 56×7= 392 км поезд прошёл за 7 часов
2) 603+392= 995 км всего
1) 43/56-11/24=129/168-77/168=52/168=13/42
2) 1 8/13×13/42=21/13×13/42=1/2
3) 5 5/7:8/21=40/7×21/8=15
4)15+1/2=5 1/2
<span>1) 2 4/11-1= 26/11- 11/11= 15/11=1 4/11 ;
2) 2 4/11-1 7/11= 26/11-18/11= 8/11 </span>
<span>1) -32+(+35)+(-36)+(+12) = -32+35-36+12 = -21
</span><span>2) 46+(-60)+(-54)+(-50) = 46-60-54-50 = -118
3) </span><span>-54+(-0,7)+(+0,56)+(-1,74) = -54-0,7+0,56-1,74 = -55,88
</span><span>4) 4 3/8 +(-1 1/4)+(-6 1/4)+(+1/4) = 4 3/8 - 1 1/4 - 6 1/4 + 1/4 = </span>4 3/8 - 7 2/8 = 2 7/8