Пошаговое объяснение:
1) 5 (×-1)+7=3 (×+1)+1
5x -5 +7 = 3x + 3 + 1
5x + 2 = 3x + 4
5x - 3x - 4 + 2 = 0
2x - 2 = 0
2x = 2
x = 2 / 2
x = 1
ответ: x = 1
2)2 (×+1)+3=3 (×-1)+6
2x + 2 + 3 = 3x -3 + 6
2x + 5 = 3x + 3
2x - 3x + 5 - 3 = 0
-x + 2 = 0
-x = -2
x = 2
ответ: x = 2
3)3 (3×+5) - 4 (3×-5)=0
9x + 15 - 12x + 20 = 0
-3x + 35 = 0
3x = 35
x = 35 / 3
ответ: x = 35 / 3
4)7 (5-×)+2=5 (6-×)+1
35 - 7x + 2 = 30 - 5x + 1
37 - 7x = 31 - 5x
37 - 7x - 31 + 5x = 0
6 - 2x = 0
2x = 6
x = 6/2
x = 3
ответ: x = 3
5)4 (×-3)-3 (×+2)=-19
4x - 12 - 3x - 6 = -19
x - 18 = - 19
x = -19 + 18
x = -1
ответ: x = -1
6)2×+1+3 (×-2)=14
2x + 1 + 3x - 6 = 14
5x -5 = 14
5x = 14 + 5
5x = 19
x = 19 / 5
ответ: x = 19 / 5
7) -5 (7-×)-4 (×-8)=3
-35 + 5x - 4x + 32 = 3
-3 + x = 3
x = 3+3
x = 6
ответ: x = 6
8) 2(×-4)-5 (×-6)=1
2x - 8 - 5x + 30 = 1
-3x + 22 = 1
-3x = 1 - 22
-3x = - 21
x = 21 / 3
x = 7
ответ: x = 7
Вроде всё так.
Удачи))
7/5*(2 7/14) = 7/5 * 35/14 = 7/2 = 3 1/2
1/9 * 1 5/6 + 1 1/6 * 1/9 = 1/9 * (1 5/6 + 1 1/6) = 1/9 * 3 = 3/9 = 1/3
1 3/8 * 3/5 - 3/5 * 1/8 = 3/5 * (1 3/8 - 1/8) = 3/5 * 1 2/8 = 3/5 * 10/8 = 6/8 = 3/4