1.запишите разность двух выражений и её. 1) -5.6+m и m+3.8 2) a-b и -b+a -c 3 -5.3+1.8-x и 1.8-x-1.4 2. раскройте скобки и выражение. 3) c+(-c+d) 4) (a+1.+2.4) 5) -(3.4-x)+(-x+1.6) 6) -(x-2.7+.5-x)
7 3/10+ 25/28 х =8 13/35 25/28 х = 293/35-73/10 25/28 х = 293/35-73/10 25/28 х = (586-511)/70 25/28 х = 75/70 х = (75*28)/(70*25) х = 6/5 = 1 1/5 = 1,2
3 1\3 - 1 1/20 х = 1 14/15 -21/20 х = 29/15-10/3 -21/20 х = (29-50)/15 21/20 х = 21/15 х = (21*20)/(15*21) = 4/3 = 1 1/3
3/8 х + 7/12 х - 5/6 х = 9/32 ((3*3+7*2-5*4)/24) х = 9/32 3/24 х = 9/32 1/8 х = 9/32 х = 9/32 : 1/8 х = (9*8)/(32*1) = 9/4 = 2 1/4 = 2,25
2 1\3 : х - 1 1/6 = 1 5/9 7/3 :х = 14/9 + 7/6 7/3 : х = (28+21)/18 7/3 : х = 49/18 х = 7/3 : 49/18 = (7*18)/(3*49) = 7/7
2 1/3 :( х - 1 1/6) = 1 5/9 7/3 : х - 7/3 : 7/6 = 14/9 7/3 : х - 2 = 14/9 7/3 : х = (14+18)/9 х = 7/3 : 32/9 = (7*9)/(3*32) = 21/32
(a-b)-(-b+a-c)=a-b+b-a+c=c
(-5,3+1,8-x)-(1,8-x-1,4)=-5,3+1,8-x-1,8+x+1,4= -3.9
2) c+(-c+d)=c-c+d=d
(a+1,6)-(a+2,4)=a+1,6-a-2,4=-0,8
-(3,4-x)+(-x+1,6)=-3,4+x-x+1,6=-1,8
-(x-2,7+y)-(6,5-x)=-x+2,7-y-6,5+x=-3,8-y