Question

Помогите решить уравнения 1) 2x + 5 = 7 2) 1,3x - 0,8 = 1,8 3) (x+1,1) - 4 = 9 4) 20 - (x - 0,7) = 4 5) 3x - 5 =13 6) 8+ 12x = 20 7) 21-5x= 11 8) 1 - x = 9 7 9) 8x=0,4 10) 3x = 4

Answer 1

Ответ:

1) 2x+5=7

2x=7-5

2x=2

x=2:2

x=1

2)1,3x-0,8=1,8

1,3x=2,8+0,8

1,3x=2,6

x=2,6:1,3

x=2

3)(x+1,1)-4=9

x+1,1=9+4

x+1,1=13

x=13-1,1

x=11,9

5)3x-5=13

3x=13+5

3x=18

x=18:3

x=6

6)8+12x=20

12x=20-8

12x=12

x=12:12

x=1

7)21-5x=11

5x=21-11

5x=10

x=10:5

x=2

9)8x=0,4

x=8:0,4

x=20

Пошаговое объяснение:

Не успела сделать 4, 8, 10

Answer 2

1) 2x + 5 = 7 2x = 7 - 5 2x = 2 x = 2/2 x = 1

2) 1.3x - 0.8 = 1.8 1.3x = 1.8 + 0.8 1.3x = 2.6 x = 2.6/1.3 x = 2

3) x + 1.1 - 4 = 9 x - 2.9 = 9 x = 9 + 2.9 x = 11.9

4) 20 - (x - 0.7) = 4 20 - x + 0.7 = 4 20 + 0.7 - 4 = x x = 16.7

5) 3x - 5 = 13 3x = 13 + 5 3x = 18 x = 18/3 x = 6

6) 8 + 12x = 20 12x = 20 - 8 12x = 12 x = 12/12 x = 1

7) 21 - 5x = 11 -5x = 11 - 21 -5x = -10 x = -10/-5 x = 2

8) 1 - x = 9 -x = 9 - 1 -x = 8 x = -8

9) 8x = 0.4 x = 0.4/8 x = 0.05

10) 3x = 4 x = 4/3 x = 1.33

Итак, решения уравнений: 1) x = 1 2) x = 2 3) x = 11.9 4) x = 16.7 5) x = 6 6) x = 1 7) x = 2 8) x = -8 9) x = 0.05 10) x = 1.33