(i) Find the equation of line joining (1,2) and (3,4) using determinants,
(ii) Find the equation of the line joining (3,1) and (9,3) using determinants.

Explanation

To find the equations of the lines joining the given points using determinants, we can follow these steps:

### (i) Find the equation of the line joining (1, 2) and (3, 4):

1. **Set up the determinant**: We will use the determinant formula for the points (x1, y1), (x2, y2), and (x, y) which gives us the area of the triangle formed by these points. The determinant is given by:

\[
\Delta = \begin{vmatrix}
...