## Lesson goal: The distance formula with variables

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In a past lesson, the distance formula as covered, which is $d=\sqrt{(x-x_0)^2+(y-y_0)^2}$. This formula will tell you the "straight line" distance between any two points on a cartesian coordinate system. As this formula is stated, one point will be $(x,y)$ and the other will be $(x_0,y_0)$.

The implementation in the past lesson was a bit cumbersome. Using variables makes it much more convenient. In this lesson, we'll see if you can program and use the distance formula using variables.