POSITION OF A POINT W.R.T. A LINE :
If the points `P(x_1, y_1)` and `Q(x_2, y_2)` lies on the same side
of the line `Ax + Bx + C=O` then the express ions
`Ax_1 + By_1 + C` and `Ax_2+ By_2 + C` will be of the same sign
and if `P(x_1 , y_1)` and `Q(x_2 , y_2)` are on the opposite side
of the line then the expressions `Ax_1 + By_1 + C`
and `Ax_2 + By_2 + C` will be of opposite sign.
of the line `Ax + Bx + C=O` then the express ions
`Ax_1 + By_1 + C` and `Ax_2+ By_2 + C` will be of the same sign
and if `P(x_1 , y_1)` and `Q(x_2 , y_2)` are on the opposite side
of the line then the expressions `Ax_1 + By_1 + C`
and `Ax_2 + By_2 + C` will be of opposite sign.