How do I find the distance between two points?

1 Answer
Jul 30, 2015

Answer:

Use distance formula or Pythagorean Theorem

Explanation:

The formula is d=#sqrt((x_1-x_2)^2+(y_1-y_2)^2)#
if point A is (#x_1,y_1#) and point B is (#x_2,y_2#)

You can actually derive this from the Pythagorean Theorem. It's tough to show here, but set up a right triangle, connect Points A and B with a point C containing the right angle (#x_2,y_1#). Then one leg will have length #x_2-x_1# and the other leg will have length #y_2-y_1#. Using Pythagorean Theorem, you can take the sum of the lengths squared, take the square root, and that gives you the formula above.

Example: Points (2, -3) and (-1, 5)

#d=sqrt((2-(-1))^2+(-3-5)^2)#
=#sqrt((3)^2+(-8)^2)#
=#sqrt(9+64)=sqrt(73)#