Question

If the distance between the points (2, –2) and (–1, x) is 5, then the values of x are ______.

Answer 1

If the distance between the points (2, –2) and (–1, x) is 5, then the values of x are 2, –6.

Explanation:

Use the distance formula:

`sqrt((-1 - 2)^2 + (x - (-2))^2) = 5`

⇒ `sqrt(9 + (x + 2)^2) = 5` 

⇒ 9 + (x + 2)² = 25 

⇒ (x + 2)² = 16

⇒ x + 2 = ±4

⇒ x = 2 or x = –6