4x – 10=2(4–x); =
8t - 5(t-6)= 39; =
2(a + 3) = 30-a; =
45 - 2(3x - 8) = 25; =
2(15 + 8x)-3(5x - 7) = 82; =

1)

4x - 10 = 2(4 - x)

4x - 10 = 8 - 2x

4x + 2x = 8 + 10

6x = 18

x = 3

ответ: 3

2)

8t -5(t - 6) = 39

8t - 5t + 30 = 39

3t = 39 - 30

3t = 9

t = 3

ответ: 3

3)

2(a + 3) = 30 - a

2a + 6 = 30 - a

2a + a = 30 - 6

3a = 24

a = 8

ответ: 8

4)

45 - 2(3x - 8) = 25

45 - 6x + 16 = 25

-6x = 25 - 16 - 45

-6x = -36

x = 6

ответ: 6

5)

2(15 + 8x) - 3(5x - 7) = 82

30 + 16x - 15x + 21 = 82

x + 51 = 82

x = 82 - 51

x = 31

ответ: 31

3;   3;   8;   6;  31

Пошаговое объяснение:

1.  4х - 10 = 2(4-х)

4х - 10 = 8 - 2х

6х = 18

х = 18:6

х = 3

2.   8t - 5(t - 6) = 39

8t - 5t + 30 = 39

3t = 39 - 30 = 9

t = 9 : 3

t = 3

3.   2(a + 3) = 30-a

2а + 6 = 30 - а

3а = 30 - 6 = 24

а = 24 : 3

а = 8

4.   45 - 2(3x - 8) = 25

45 - 6х + 16 = 25

-6х = 25 -45 -16 = -36

х = 36 : 6

х = 6

5.   2(15 + 8x) - 3(5x - 7) = 82

30 + 16х - 15х + 21 = 82

х = 82 - 21 - 30

х = 31