Question

13). 0,3(8 – 3у) = 3,2 – 0,8(у - 7) 14). 4(х - 1) = 2(2х - 8) + 12 15). 8(5 – 3х) = 6(2 – 4х) + 7

Answer 1

Ответ:

Пошаговое объяснение:

13).

0,3(8 – 3у) = 3,2 – 0,8(у - 7)

2,4 - 0,9y = 3,2 - 0,8y + 5,6

2,4 - 0,9y = 8,8 - 0,8y

0,9y - 0,8y = 2,4 - 8,8

0,1y = -6,4

y = -6,4 : 0,1

y = -64

14).

4(х - 1) = 2(2х - 8) + 12

4x - 4 = 4x - 16 + 12

4x - 4 = 4x -4

4x - 4x = 4 - 4

0 = 0

x є (-∞ ; ∞)

15).

8(5 – 3х) = 6(2 – 4х) + 7

40 - 24x = 12 - 24x + 7

40 - 24x = 19 - 24x

24x - 24x = 19 - 40

0 ≠ -21

уравнение не имеет корней

Answer 2

Let's solve each equation step by step:

13. 0.3(8 - 3y) = 3.2 - 0.8(y - 7)

First, distribute 0.3 to the terms inside the parentheses:

2.4 - 0.9y = 3.2 - 0.8(y - 7)

Next, distribute -0.8 to the terms inside the parentheses:

2.4 - 0.9y = 3.2 - 0.8y + 5.6

Combine like terms:

-0.9y + 0.8y = 3.2 + 5.6 - 2.4

-0.1y = 6.4

Divide both sides of the equation by -0.1 to solve for y:

y = 6.4 / -0.1

y = -64

Therefore, the solution for equation 13 is y = -64.

14. 4(x - 1) = 2(2x - 8) + 12

First, distribute 4 to the terms inside the parentheses:

4x - 4 = 4x - 16 + 12

Combine like terms:

4x - 4 = 4x - 4

The equation simplifies to 0 = 0. This means that the equation is an identity, which implies that any value of x would satisfy the equation.

Therefore, for equation 14, there are infinitely many solutions.

15. 8(5 - 3x) = 6(2 - 4x) + 7

First, distribute 8 to the terms inside the parentheses:

40 - 24x = 12 - 24x + 7

Combine like terms:

-24x + 24x = 12 + 7 - 40

0 = -21

The equation simplifies to 0 = -21, which is not a true statement. This means that there is no solution to this equation.

Therefore, for equation 15, there is no solution.