Question

1) 7x - (3 + 2x) = x + 9; 2) 13 - (2x - 5) = x - 3;3) 3x – (10 - 9x) = 223;4) 26 - (17 – 2x) = 5x.​

Answer 1

Ответ:

Пошаговое объяснение:

1) 7x - (3 + 2x) = x + 9;

7x - 3 - 2x = x + 9

5x - 3 = x + 9

5x - x = 9 + 3

4x = 12

x = 12 : 4

x = 3

2) 13 - (2x - 5) = x - 3;

13 - 2x + 5 = x - 3

18 - 2x = x - 3

x + 2x = 18 + 3

3x = 21

x = 21 : 3

x = 7

3) 3x – (10 - 9x) = 223;

3x - 10 + 9x = 223

12x - 10 = 223

12x = 223 + 10

12x = 233

x = 233 : 12

x = 19 5/12

4) 26 - (17 – 2x) = 5x.​

26 - 17 + 2x = 5x

9 + 2x = 5x

5x - 2x = 9

3x = 9

x = 9 : 3

x = 3

Answer 2

Let's solve each of the equations step by step:

1. 7x - (3 + 2x) = x + 9

First, distribute the negative sign inside the parentheses: 7x - 3 - 2x = x + 9

Combine like terms: (7x - 2x) - 3 = x + 9 5x - 3 = x + 9

Move the x term to one side and the constant terms to the other side: 5x - x = 9 + 3 4x = 12

Divide both sides by 4 to solve for x: x = 12 / 4 x = 3

So the solution to the equation is x = 3.

2. 13 - (2x - 5) = x - 3

First, distribute the negative sign inside the parentheses: 13 - 2x + 5 = x - 3

Combine like terms: 18 - 2x = x - 3

Move the x term to one side and the constant terms to the other side: 18 + 3 = x + 2x 21 = 3x

Divide both sides by 3 to solve for x: x = 21 / 3 x = 7

So the solution to the equation is x = 7.

3. 3x – (10 - 9x) = 223

First, distribute the negative sign inside the parentheses: 3x - 10 + 9x = 223

Combine like terms: 12x - 10 = 223

Move the constant term to the other side: 12x = 223 + 10 12x = 233

Divide both sides by 12 to solve for x: x = 233 / 12

So the solution to the equation is x ≈ 19.4167 (rounded to four decimal places).

4. 26 - (17 – 2x) = 5x

First, distribute the negative sign inside the parentheses: 26 - 17 + 2x = 5x

Combine like terms: 9 + 2x = 5x

Move the x term to one side and the constant term to the other side: 2x - 5x = -9 -3x = -9

Divide both sides by -3 to solve for x: x = (-9) / (-3) x = 3

So the solution to the equation is x = 3.