Question

Помогите пж Системы двух уравнений с двумя неизвестными (2x-y=3 (7x+3y=4 (x-5y=11 (3x-5y=13

Answer 1

7x-3y=13    
x=5+2y

7(5+2y)-3y=13       x=5+2(-2)
35+14y-3y=13       x=1
11y=-22
 y=-2 

Answer 2

Solving the System of Equations:

To solve the system of equations, we can use the method of substitution or elimination. Let's use the method of substitution to solve the given system of equations:

1. Equations: - 2x - y = 3 - 7x + 3y = 4

2. Solving for y in the first equation: - From the first equation, we can express y in terms of x: y = 2x - 3.

3. Substituting y in the second equation: - Now, we substitute the value of y in the second equation: 7x + 3(2x - 3) = 4.

4. Solving for x: - Simplifying the equation: 7x + 6x - 9 = 4 - Combining like terms: 13x - 9 = 4 - Adding 9 to both sides: 13x = 13 - Solving for x: x = 1.

5. Finding the value of y: - Substituting x = 1 in the first equation: 2(1) - y = 3 - Simplifying: 2 - y = 3 - Solving for y: y = -1.

6. Solution: - The solution to the system of equations is x = 1 and y = -1.

Therefore, the solution to the given system of equations is x = 1 and y = -1.