How do you calculate the distance between 2 points given its coordinates?

Sorry, this page requires a Java-compatible web browser.

Where does the formula to calculate the distance come from?

• Hide the distance from A to B 
• Drag A and/or B to new positions
• Calculate the distance
• Check your answer

Practice finding the distance between 2 points.
IMPORTANT: If answer is not exact give it correct to 2 decimal place.
You'll need a calculator for this one.

Just for the rush -- add a Timer to challenge against the clock.