Pythagoras

Hard

$ABCD\,$ is a right-angled trapezium where $AB\,$ is parallel to $DC\,$ and $AD\,$ is perpendicular to both parallel sides.

Diagram of a trapezium ABCD with side AB = 10 cm, side BC = 17 cm, and side DC = 18 cm.

$A B = 10$ cm, $B C = 17$ cm, and $D C = 18$ cm.

Calculate the length of $A D$ .

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Pythagoras Questions