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Distance of a Point from a Line (of a point to a line)

What do we mean by distance of a point from a line or distance of a point to a line?

Distance of a Point to a Line

Exploration

What is the distance of point A (4, 4) to the line CD (or distance of point A from the line CD)? Is it the same as the length of the line segment AB What is the length of the line segment AB ?

If we move point B on the line CD, is the length AB now changed?

Is there a particular distance that is the shortest between point A at (4, 4) and the line CD? Keep moving point B until you find the shortest distance. What is the shortest distance ?

What is the angle between AB and CD when the shortest distance of AB is achieved?

Now shift point A to (7, 5). What is the distance of point A from the line CD , using the distance AB now?

Move point B on the line CD again. Has the distance of the point B from the line CD changed?

Is there a particular distance that is shortest between point A at (7, 5) and the line CD? What is the shortest distance between A and the line CD?

What is the angle between AB and CD when this occurs?

Conclusion What can we say about the distance of a point A to a line (or distance of a point from a line) ?