Midpoint

Midpoint

The midpoint of two points A & B is the point that lies on line segment AB that is equidistant to both endpoints.

Think of it as the "average of two points".

Explore!

Use the applet below to explore the formula for midpoint of 2 points A and B.

Perpendicular Bisector

The perpendicular bisector of two points A & B is the line that passes through line segment AB that is equidistant to both endpoints.

4 Steps to find Perpendicular Bisector

Step 1: Find the midpoint of AB.

Step 2: Find the gradient of AB.

Step 3: Find the gradient of the perpendicular line.

Step 4: Find the y-intercept of the perpendicular line by substituting the midpoint (Step 1) and perpendicular gradient (Step 3) into the equation

y = mx + c.