Question

1) 7x=14,1+5x 2) 3/4x-12,5=1 1/8x-1/2 3) -0,4x-14=0,3x 4) 7,05-x=5 5) -60(x-3)=360 6) 6,9-9x=-5x-33,1 7) (5-34)*2,1=42 8) 11-5(2x+1)=16 9) 8,4-(x-7,2)=8,6

Answer 1

1) x = 7,05
2) x = -71/9
3) x = -20
4) x = 2,05
5) x = -3
6) x = 10
7) -60,9 = 42
равенство неверно, поскольку его левая и правая части различны
8) x = -1
9) x = 7

Answer 2

Let's solve the equations one by one:

1. 7x = 14.1 + 5x

To solve this equation, we want to isolate the variable x on one side of the equation. We can do this by subtracting 5x from both sides:

7x - 5x = 14.1

Combining like terms:

2x = 14.1

Finally, we divide both sides by 2 to solve for x:

x = 14.1 / 2

x = 7.05

2. 3/4x - 12.5 = 1 1/8x - 1/2

To simplify this equation, let's convert the fractions into a common denominator. The common denominator for 4 and 8 is 8:

(3/4)x - 12.5 = (1/8)x - 1/2

Multiplying both sides by 8 to eliminate the fractions:

2x - 100 = x - 4

Now, we can isolate the x term on one side by subtracting x from both sides:

2x - x = 100 - 4

x = 96

3. -0.4x - 14 = 0.3x

First, let's eliminate the decimals by multiplying both sides by 10:

(-0.4)x - 14 = (0.3)x

-4x - 140 = 3x

Now, let's isolate the x term on one side by adding 4x to both sides:

-4x + 4x - 140 = 3x + 4x

-140 = 7x

Finally, we solve for x by dividing both sides by 7:

x = -140 / 7

x = -20

4. 7.05 - x = 5

To solve this equation, we can isolate the x term by subtracting 7.05 from both sides:

7.05 - x - 7.05 = 5 - 7.05

-x = -2.05

Multiplying both sides by -1 to solve for x:

x = 2.05

5. -60(x - 3) = 360

To solve this equation, we can start by distributing -60 to the terms inside the parentheses:

-60x + 180 = 360

Next, let's isolate the x term by subtracting 180 from both sides:

-60x + 180 - 180 = 360 - 180

-60x = 180

Dividing both sides by -60 to solve for x:

x = 180 / -60

x = -3

6. 6.9 - 9x = -5x - 33.1

To solve this equation, let's isolate the x terms on one side and the constant terms on the other side:

-9x + 5x = -33.1 - 6.9

-4x = -40

Dividing both sides by -4 to solve for x:

x = -40 / -4

x = 10

7. (5 - 34) * 2.1 = 42

To solve this equation, we can simplify the expression inside the parentheses:

(-29) * 2.1 = 42

Now, let's multiply -29 by 2.1:

-60.9 = 42

This equation is not true since -60.9 is not equal to 42. Therefore, there is no solution.

8. 11 - 5(2x + 1) = 16

To solve this equation, let's distribute -5 to the terms inside the parentheses:

11 - 10x - 5 = 16

Simplifying the equation:

6 - 10x = 16

Next, let's isolate the x term by subtracting 6 from both sides:

-10x = 16 - 6

-10x = 10

Dividing both sides by -10 to solve for x:

x = 10 / -10

x = -1

9. 8.4 - (x - 7.2) = 8.6

Let's start by simplifying the expression inside the parentheses:

8.4 - x + 7.2 = 8.6

Combining like terms:

15.6 - x = 8.6

Next, let's isolate the x term by subtracting 15.6 from both sides:

• x = 8.6 - 15.6

• x = -7

Multiplying both sides by -1 to solve for x:

x = 7

Please double-check the calculations for any potential errors.