Answer:
D = √[(x2 - x1)² + (y2 - y1)²]
Step-by-step explanation:
Given a right-angled triangle, with sides: Hypotenuse D, and opposites (x2 - x1) and (y2 - y1).
Then by Pythagoras theorem, the square of the hypotenuse is equal to the sum of the squares of the opposite side.
That is,
D² = (x2 - x1)² + (y2 - y1)²
Now, taking square roots of both side, we have the formula for the distance or length D.
D = √[(x2 - x1)² + (y2 - y1)²]
