# Calculate point on hypotenuse of right-angled triangle

Sorry if this is a little basic, but my math is pretty rusty. I know the point coordinates of the two blue dots. I also know the distances from the middle blue dot to the edges of the square. How can I calculate the coordinates of the red dot?

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The two right angled triangles in the picture are similar. Hence the ratio of the corresponding sides are the same. You can use this to get the remaining coordinates.

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