People usually forget a formula to find a distance between two points. The thing is that, you don’t need to memorize the formula if you know where the formula comes from.
The key essence to find the distance between two point is Pythagorean Theorem. If you have a right triangle, the square of hypotenuse is equal to sum of squares of other two sides.
a^2 + b^2 = c^2
If you know this equation you don’t needs to worry about formula for the distance between two points.
For example, let’s find the distance between (2,4) and (5,8).
You should connect these two points, then the length of the line should equal to distance between two points.
Then you should make a right triangle with the line as a hypotenuse.
(5,8) |
__….|
(2,4)|__ (5,4)
Like this. Then you can easily get the other two sides. By subtracting.
One side is 5 – 2 = 3
The other side is 8 – 4 = 4
So now, you got a right triangle with two sides, so you can easily find the hypotenuse.
Hypotenuse = square root of (3^2 + 4^2) = square root of 25 = 5
Previously, I said the hypotenuse is the distance between two points, so the distance between two point (2,4) and (5,8) is 5.
The general formula for getting distance between (a,b) and (c,d) is
R = square root of ((c-a)^2 + (d-b)^2)
Where R is the distance between two points.
This article was written for you by Edmond, one of the tutors with SchoolTutoring Academy.