Ответ:
1) Б
2) Г
3) А
4) А
5) 1 В 2 Г 3 Д 4 Б
6) 2,6x * 100y * (-1/13z) = 260xy * (-1/13z) = -20xyz
7) 5 : 1/5 + 3 : (-0.1) + 14 = 25 - 30 + 14 = -5 + 14 = 9
8) 2 2/3 : (-3 1/3) = x : 3.5
8/3 : (-10/3) = x : 3.5
-(8 * 3)/(3 * 10) = x : 3.5
-24/30 = x : 35/10
-0.8 * 3.5 = x
x = -2.8
9) Перед 4 минус или тире? Если тире:
4(3.6x - 2) - (3 - 2.1x) + 5(0.3x - 6) = 14.4x - 8 - 3 + 2.1x + 1.5x - 30 = 18x - 41
x = -5/27
18 * (-5/27) - 41 = -10/3 - 41 = -(10 - 123)/3 = 113/3 = 37 2/3
Если минус:
-4(3.6x - 2) - (3 - 2.1x) + 5(0.3x - 6) = -14.4x + 8 - 3 + 2.1x + 1.5x - 30 = -10,8x - 25
x = -5/27
-10,8 * (-5/27) - 25 = 2 - 25 = -23
10) (-1 3/7 * 4 2/3 + 1 7/9) * (-3/4) = (-10/7 * 14/3 + 16/9) * (-3/4) = (-20/3 + 16/9) * (-3/4) = -(60+16)/9 * (-3/4) = 76/9 * 3/4 = 19/3
Пошаговое объяснение: