Question

Помогите пожалуйста с домашним:(

Answer 1

Ответ:

1) 7x + 5 = 5x + 7

7x - 5x = 7 - 5

2x = 2

x = 2 / 2

x = 1

2) 4x = x + 2(3x+5)

4x = x + 6x + 10

4x - x - 6x = 10

-3x = 10

-x = $\frac{10}{3}$

x = $-\frac{10}{3}$ или $-3\frac{1}{3}$

3) 4(2x - 5) - x = 3x + 8

8x - 20 - x = 3x + 8

8x - x - 3x = 8 + 20

4x = 28

x = 28 / 4

x = 7

4) 7(3x - 2) - 6(4x + 7) = 18x

21x - 14 - 24x - 42 = 18x

21x - 24x - 18x = 42 + 14

-21x = 56

-x = $\frac{56}{21}$

x = $- \frac{56}{21}$ сокращаем на 7 и получаем $-\frac{8}{3}$ = $2 \frac{2}{3}$

5) 2(6x - 5) - 5(3x + 4) = 7x - 10

12x - 10 - 15x - 20 = 7x - 10

12x - 15x - 7x = -10 + 20 + 10

-10x = 20

-x = 20 / 10

-x = 2

x = -2