Question

DISTANCE EQUATION
i know it is the first one but what other ones?

Answer 1

A and E

Explanation:

d =
`\sqrt{(x_(2)-x_(1))^2+(y_(2)-y_(1))^2 }` ← distance formula

it is important that the x and y coordinates are placed correctly, that is not mixed together.

First version

let (x₁, y₁ ) = X (- 5, 4 ) and (x₂, y₂ ) = Y (7, 15 ) , then

XY =
`√((7-(-5)^2+(15-4)^2)` → A

or

Second version

let (x₁, y₁ ) = Y (7, 15 ) and (x₂, y₂ ) = X (- 5, 4 ) , then

XY =
`√((-5-7)^2+(4-15)^2)` → E