In coordinate geometry, a line can be described using various forms depending on the given points, slope, or other line characteristics.
\[ \frac{y - y_1}{y_2 - y_1} = \frac{x - x_1}{x_2 - x_1} \]
Point: \( A(x_0, y_0) \), Given Line: \( y = ax + b \)
\[ y - y_0 = a(x - x_0) \]
Point: \( A(x_0, y_0) \), Given Line: \( y = ax + b \)
\[ y - y_0 = -\frac{1}{a}(x - x_0) \]