9514 1404 393
Answer:
11.6 cm
Explanation:
As the page title tells you, the Pythagorean theorem must be applied more than once. As you know, it tells you the square of the hypotenuse is the sum of the squares of the two sides.
AD² = ED² +EA²
EA² = AD²-ED² = 7² -6² = 13
EA = √13 ≈ 3.606
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CD² = ED² +EC²
EC² = CD² -ED² = 10² -6² = 64
EC = √64 = 8
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The length of the horizontal diagonal is ...
AC = EA +EC = 3.6 +8 = 11.6 . . . cm