№1024.
-5(3х+7-t) = - 15x - 35 + 5t
(1.2a+ 3.4b + 2) * 3 = 3.6a + 10.2b +6
-(4a -5b -3) = -4a +5b +3
0.7(x+0.5y - 1) = 0.7x + 0.35y - 0.7
- (8x+y-9) = - 8x - y + 9
(2x - 4t + z) * (-2) = - 4x + 8t - 2z
a(3x-y+z) = 3ax -ay +az
2a(x-3y +2z) = 2ax -6ay +4az
-6(2/3 *x - 1/2 * y + 1/4 *z ) = - 12/3 * x + 6/2 * y - 6/4 *z =
= -4x + 3y - 1.5z
-m(2n- 3x+1) = - 2mn +3mx -m
(a-3b+5c) * (-2m) = - 2am +6bm - 10cm
15 *(1/2 *a + 2/3 * b - 1/5 *c ) = 7.5a + 10b - 3c
№ 1025.
5 * (-95) = 5 * (-90 - 5 ) = - 450 - 25 = -475
24 * (-99) = 24 * (- 100 + 1) = -2400 + 24 = -2376
9 * (-98) = 9 * ( -100 + 2) = -900 + 18 = -882
-9 * 101 = - 9 * (100+1) = - 900 - 9 = - 909
67 * 1002 = 67 * (1000 + 2) = 67000 + (60+7)* 2 = 67000 + 120 + 14 = 67134
19 *(-103) = 19 *(-100 - 3 )= -1900 + (10+9) * (-3) = - 1900 - 300 - 27 =-2227
17 * 102 = 17 * (100+2) = 1700 + 34 = 1734
-67 * 1002 = - 67 *(1000 + 2) = -67000 - 134 = -67134
-24 * 99 = - 24 * (100 - 1) = -2400 + 24 = -2376
№1026.
54*36 - 42 * 54 + 6 * 74 =54 * 36 - 54 * 42 + 6*54 + 6*20 =
= 54 * (36 - 42 + 6) + 120 = 54*0 + 120 = 120
478 * 62 + 13 * 478 - 75 * 678 =
=478 * 62 + 478*13 - 478 * 75 - 200 * 75 =
= 478 * (62 + 13 - 75) - (70 + 5) * 200 =
= 478 * 0 - ( 70*200 + 5*200) = - 14000 -1000=
= -15000