How to find the coordinates of the point of intersection of lines: x-y = -1 and 2x + y = 4.

To determine the point of intersection, we will solve the system consisting of these equations.

1. Add the 2nd to the 1st equation and find the value of x:

x – y + 2 x + y = -1 + 4;

3 x = 3;

x = 3: 3;

x = 1.

2. Determine the value of y:

x – y = -1;

y = x + 1 = 1 + 1 = 2.

3. Check:

1 – 2 = -1;

2 1 + 2 = 4.

Answer: x = 1, y = 2.