Question

If the distance between the points A(4, p) and B(1, 0) is 5 then ______.

Options

• p = 4 only

• p = –4 only

• p = ±4

• p = 0

Answer 1

If the distance between the points A(4, p) and B(1, 0) is 5 then p = ±4.

Explanation:

Use the distance formula:

`sqrt((4 - 1)^2 + (p - 0)^2) = 5` 

⇒ `sqrt(9 + p^2) = 5` 

Square both sides:

9 + p² = 25 

⇒ p² = 16

⇒ p = ±4