$[$ [Properties and characteristics of a parallelogram]

A line has only one common point $B$ with parallelogram $A B C D$. Vertices $A$ and $C$ are at distances $a$ and $b$ from this line, respectively.

At what distance is vertex $D$ from this line?

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The center $O$ of the parallelogram is at a distance of $1 / 2(a+b)$ from the line, and vertex $D$ is twice as far.

## Answer

$a+b$.

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The center $O$ of the parallelogram is at a distance of $1 / 2(a+b)$ from the line, and vertex $D$ is twice as far.

## Answer

$a+b$.