Let ax + by + c = 0 be a given straight line and P (x₁ , y₁ ) be a given point. If ax₁ + by₁ + c is positive,

then the side of the straight line on which the point P lies is

called the positive (outside) side of the line and the other side is called its negative (inside) side.

Again if ax₁ + by₁ + c = c, then it is evident that the origin is on the positive side of the line ax + by + c = 0

when c is positive and the origin is on the negative side of the line when c is negative.

Now, given line is: x - y - 2 = 0 and point is (2, 3)

So, x - y - 2 = 2 - 3 - 2 = -3 < 0

So, the point (2, 3) lies negative (inside) side of the line x - y - 2 = 0