Question

1) 7(х +3 ) = 2(х+6) 2) 4(2-х )= 6х+283) 8(2х – 1) – 5(3х + 0,8) = х-44) 8х + 40 = 100 + 2х5) 3,5 – 3х = 2,3 + х​

Answer 1

Ответ:

1) 7x + 21 = 2x + 12

7x - 2x = 12 - 21

5x = -9

x = -(9 + 5)

x = -14

2) 8 - 4x = 6x + 28

8 - 28 = 4x + 6x

-20 = 10x

x = -20 ÷ 10

x = -2

Answer 2

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

1. 7(x + 3) = 2(x + 6)

First, distribute the numbers outside the parentheses:

7x + 21 = 2x + 12

Now, move all the terms containing 'x' to one side of the equation and the constants to the other side:

7x - 2x = 12 - 21

Combine like terms:

5x = -9

Now, divide both sides by 5 to isolate 'x':

x = -9/5 or x = -1.8

2. 4(2 - x) = 6x + 28

First, distribute the numbers outside the parentheses:

8 - 4x = 6x + 28

Now, move all the terms containing 'x' to one side of the equation and the constants to the other side:

-4x - 6x = 28 - 8

Combine like terms:

-10x = 20

Now, divide both sides by -10 to isolate 'x':

x = -20/10 or x = -2

3. 8(2x - 1) - 5(3x + 0.8) = x - 4

First, distribute the numbers outside the parentheses:

16x - 8 - 15x - 4 = x - 4

Now, move all the terms containing 'x' to one side of the equation and the constants to the other side:

(16x - 15x - x) - (8 + 4) = -4

Combine like terms:

0x - 12 = -4

Now, add 12 to both sides of the equation:

0x = -4 + 12

0x = 8

Since the coefficient of 'x' is 0, there is no 'x' term left. This means the equation is satisfied for all values of 'x'.

4. 8x + 40 = 100 + 2x

First, move the terms containing 'x' to one side of the equation and the constants to the other side:

8x - 2x = 100 - 40

Combine like terms:

6x = 60

Now, divide both sides by 6 to isolate 'x':

x = 60/6

x = 10

5. 3.5 - 3x = 2.3 + x

First, move the terms containing 'x' to one side of the equation and the constants to the other side:

-3x - x = 2.3 - 3.5

Combine like terms:

-4x = -1.2

Now, divide both sides by -4 to isolate 'x':

x = -1.2 / -4

x = 0.3

So, the solutions for the equations are as follows:

1. x = -1.8
2. x = -2
3. The equation has no solution.
4. x = 10
5. x = 0.3