Line calculators (fixed)

Rewritten by Miriam because the guy who originally wrote these didn't even bother to check if they work. Both parts were not only loaded with bad grammar and spelling mistakes, but mathematically they were just plain wrong!

Distance Calculator

Finds the length of a line. Just give the coordinates of the start and end points of the line.
It uses Pythagoras' formula: the square of the hypotenuse is equal to the sum of the squares on the other two sides.
D = sqr((X2-X1)2 + (Y2 - Y1)2)

( X1 , Y1 )     ( X2 , Y2 )

Mid-Point Calculator

Consider the X values separately from the Y values. Subtract the smaller X value from the larger one to get the distance along the X axis between the two values. Now divide that by 2 to get half the distance, and add that distance back to the lower value to get the midpoint along the X axis. Now do the same for the Y values: Subtract the smaller Y value from the larger one to get the distance, get half that, and add it to the lower value.

( X1 , Y1 )     ( X2 , Y2 )