Question

If A is a point on the Y-axis whose ordinate is 8 and B is a point on the X-axis whose abscissae is 5 then the equation of the line AB is

Options

• 8x + 5y = 40

• 8x – 5y = 40

• x = 8

• y = 5

Answer 1

8x + 5y = 40

Explanation;

Hint:

Let point A be (0, 8) and B (5, 0)

`(y - y_1)/(y_2 - y_1) = (x - x_1)/(x_2 - x_1)`

`(y - 8)/(0 - 8) = (x - 0)/(5 - 0)`

⇒ `(y - 8)/(-8) = x/5`

− 8x = 5y = − 40

− 8x − 5y = − 40

8x + 5y = 40