Question

3(x+y)+1=x+4y; 7 -2(x-y)=x-8y​

Answer 1

Если я правильно понял, то это система уравнений. Если нет, то надо было писать условие точнее.

Ответ:

х = -9/13, у = -5/13

Пошаговое объяснение:

3(х + у) + 1 = х + 4у

7 - 2(х + у) = х - 8у

3х + 3у + 1 = х + 4у

7 - 2х - 2у = х - 8у

2х - у = -1 (домножим на 6)

-3х + 6у = -7

12х - 6у = -6

-3х + 6у = -7

Складываем систему

9х = -13

х = -9/13

2х - у = -1

-18/13 - у = -1

у = 1 - 18/13

у = -5/13

Answer 2

To solve this system of linear equations:

1. Start with the first equation: 3(x + y) + 1 = x + 4y

2. Distribute the 3 on the left side of the equation: 3x + 3y + 1 = x + 4y

3. Move the x and 4y terms to the left side by subtracting x and 4y from both sides: 3x - x + 3y - 4y + 1 = 0

4. Simplify the equation: 2x - y + 1 = 0

Now you have the first equation in simplified form: 2x - y + 1 = 0.

Next, let's work on the second equation:

1. Start with the second equation: 7 - 2(x - y) = x - 8y

2. Distribute the -2 on the left side of the equation: 7 + 2x - 2y = x - 8y

3. Move the x and 8y terms to the left side by subtracting x and 8y from both sides: 2x - 2y - x + 8y + 7 = 0

4. Simplify the equation: x + 6y + 7 = 0

Now you have the second equation in simplified form: x + 6y + 7 = 0.

So, you have the two equations in simplified form:

1. 2x - y + 1 = 0
2. x + 6y + 7 = 0

You can now solve this system of equations for the values of x and y. There are multiple methods to solve this system, such as substitution, elimination, or using a matrix. Let's use the elimination method.

First, we'll eliminate one of the variables. To do this, we'll add the two equations together, which will eliminate the y variable:

(2x - y + 1) + (x + 6y + 7) = 0 + 0

Now, simplify:

3x + 7 = 0

Subtract 7 from both sides:

3x = -7

Now, divide by 3 to isolate x:

x = -7/3

Now that you have the value of x, you can substitute it into either of the original equations to solve for y. Let's use the first equation:

2x - y + 1 = 0 2(-7/3) - y + 1 = 0

Simplify:

-14/3 - y + 1 = 0

Now, add 14/3 to both sides:

• y + 1 + 14/3 = 0 + 14/3

Simplify:

• y + 1 + 14/3 = 14/3

Now, subtract 1 from both sides:

• y + 14/3 = 14/3 - 1

Simplify:

• y + 14/3 = 11/3

Now, subtract 14/3 from both sides to solve for y:

• y = 11/3 - 14/3

Simplify:

• y = -3/3

• y = -1

So, the solution to the system of equations is:

x = -7/3 y = -1