Distance from a point to a line

Imagine you are standing with a pencil on a road. You want to draw a line straight up from the road, but you can't see where to put your pencil exactly. You take a closer look and you notice that there's a tree nearby. You can use the tree as a reference point to figure out where to put your pencil.

Now, let's say you have a point on the road and you want to find out how far it is from that point to a line that goes straight up from the road, just like your pencil line. To do that, you need to imagine a line that goes straight through the point and is perpendicular (meaning it crosses at a right angle) to the line going up from the road. This is like drawing a line from the point to the tree that is perpendicular to the road.

Once you have drawn your perpendicular line, you can measure how long it is. This measurement is the distance from the point to the line going straight up from the road. You can use this same method to calculate the distance from any point to any line, by drawing a perpendicular line and measuring its length.