Question

What will the equation of line joining (1, 2) and (3, 6) using determinants

Options

• y = 2x

• 2y = x

• x = y

• 3x = 2y

Answer 1

y = 2x

Explanation:

Let P(x, y) can be any point on the line joining points A (1, 2) and B(3, 6).

The points A, B, and P are then collinear.

As a result, the area of triangle ABP is zero.

`1/2|(1, 2, 1),(3, 6, 1),(x, y, 1)|` = 0

⇒ `1/2 [1(6 - y) - 2(3 - x) + 1(3y - 6x)` = 0

⇒ `6 - y - 6 + 2x + 3y - 6x` = 0

⇒ `2y - 4x` = 0

⇒ `y = 2x`

As a result, the equation for the line connecting the given points is y = 2x.