Question

1)0.2-2(х+1)=0.4х 2)2/5у+3/5=1/5у-0.1 3)х-1/2=4+2х/3 4)3/4х=-7/8 5)х:(-0.15)=-0.4 6)-3×(-х)=-210 7)(2/5-1)÷3/10 Решите уравнения

Answer 1

Надеюсь вовремя))) удачи на матеше

Answer 2

Sure, I'll help you solve these equations step-by-step:

1. 0.2 - 2(x + 1) = 0.4x

First, distribute the -2:

0.2 - 2x - 2 = 0.4x

Combine like terms:

-2x - 1.8 = 0.4x

Add 2x to both sides to get x terms on one side:

-1.8 = 0.4x + 2x

Combine x terms:

-1.8 = 2.4x

Now, divide by 2.4 to solve for x:

x = -1.8 / 2.4

x = -0.75

2. 2/5y + 3/5 = 1/5y - 0.1

First, let's isolate the y term on one side. Subtract 1/5y from both sides:

2/5y - 1/5y + 3/5 = -0.1

Now, combine like terms:

1/5y + 3/5 = -0.1

Next, subtract 3/5 from both sides:

1/5y = -0.1 - 3/5

To get rid of the fraction, multiply both sides by 5:

y = (-0.1 - 3/5) * 5

Now, calculate the right-hand side:

y = (-0.1 * 5) - (3/5 * 5)

y = -0.5 - 3

y = -3.5

3. x - 1/2 = 4 + 2x/3

To get rid of the fraction, let's multiply everything by 6 (the least common multiple of 2 and 3):

6x - 3 = 24 + 4x

Now, move the x terms to one side by subtracting 4x from both sides and move the constant term to the other side by adding 3:

6x - 4x = 24 + 3

2x = 27

Now, divide by 2 to solve for x:

x = 27 / 2

x = 13.5

4. 3/4x = -7/8

To solve for x, multiply both sides by 4/3 (the reciprocal of 3/4):

x = (-7/8) * (4/3)

x = -7/6

5. x / (-0.15) = -0.4

To solve for x, multiply both sides by -0.15:

x = -0.4 * (-0.15)

x = 0.06

6. -3 × (-x) = -210

Multiply the numbers on the left side:

3x = -210

Now, divide by 3 to solve for x:

x = -210 / 3

x = -70

7. (2/5 - 1) ÷ 3/10

First, subtract 1 from 2/5:

(2/5 - 1) ÷ 3/10

= (-3/5) ÷ 3/10

To divide by a fraction, multiply by its reciprocal:

= (-3/5) * (10/3)

= -30/15

Now, simplify the fraction:

= -2

So, the value of the expression is -2.