Question

Помогите решить систему ур-ний способом подстановки и сложения х+у=7 х-у=3

Answer 1

1)х+у=7
4+3=7
2)х-у=3
95-92=3

Answer 2

Solving the System of Equations

To solve the system of equations x + y = 7 and x - y = 3 using the method of substitution and addition, we can follow these steps:

1. Solve one of the equations for one variable. 2. Substitute the expression obtained in step 1 into the other equation. 3. Solve for the remaining variable. 4. Substitute the value found in step 3 into one of the original equations to find the value of the other variable.

Let's proceed with these steps.

Step 1: Solve the second equation x - y = 3 for x: x = y + 3.

Step 2: Substitute the expression x = y + 3 into the first equation x + y = 7: (y + 3) + y = 7.

Step 3: Solve for y: 2y + 3 = 7, 2y = 7 - 3, 2y = 4, y = 2.

Step 4: Substitute the value of y into the expression x = y + 3: x = 2 + 3, x = 5.

Solution

Therefore, the solution to the system of equations x + y = 7 and x - y = 3 is x = 5 and y = 2.