Learning perpendiculars and distance in geometry will make other types of math problems a lot easier. Learn perpendiculars and distance in geometry with help from a professional private tutor in this free video clip.

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Learning perpendiculars and distance in geometry will make other types of math problems a lot easier. Learn perpendiculars and distance in geometry with help from a professional private tutor in this free video clip.

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Hi, I'm Rachel, and today we're going to be going over how to learn perpendiculars and distance in geometry. If we have a point and a line, and we want to know the difference from the points to the line, we have to draw a perpendicular line from the point to the line, and that will give us the most direct distance from the points to the line. It forms, as you can see, a 90 degree angle, because it's perpendicular, and we can draw a point right there where that intersects. And then we can use these two points to find the distance. Let's say we're on a graph here, and this will be our x1, y1 point, and this will be our x2,y2 point. So let's say this is negative 10, so let's say x1, y1 is going to be negative 10 and eight. And x2, y2 is going to be five comma, negative five comma three, for our two points. Now we use the distance formula. The distance is the square root of x2 minus x1 quantity squared, plus y2 minus y1 quantity squared, all square rooted. Now, we just plug in the points from this graph. So we get x2, right? That's negative five, minus negative 10, two negatives make a positive, so we can just say plus 10, quantity squared, plus y2 is three, minus eight squared. So we end up getting d is the square root of five squared, right? Negative five squared, but that's 25, and negative five squared is 25. So, 25 plus 25, d equals the square root of 50, and that's our distance. If you want to simplify it by saying that's, you know, four root two, you can also write it, sorry five root two, you can also write it that way as well. I'm Rachel, and thanks for learning with us today.