Find equation of line joining (3, 1) and (9, 3) using determinants.


Equation of line joining points (x1, y1) & (x2, y2) is given by = 0

Given points are (3, 1) and (9, 3)


Equation of line is given by = 0


1/2 × [3 × (3 × 1 – y × 1) – 1 × (9 × 1 – x × 1) + 1 × (9 × y – x × 3)] = 0


[3 × (3 – y) – 1 × (9 – x) + (9y – 3x)] = 0 × 2


(9 – 3y – 9 + x + 9y – 3x) = 0


6y – 2x = 0


2x – 6y = 0 x – 3y = 0


Required Equation of line is x – 3y = 0


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