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August 28, 2014

August 28, 2014

Posted by **lisa** on Saturday, April 28, 2012 at 11:07am.

- math -
**Ms. Sue**, Saturday, April 28, 2012 at 11:24amYou can use the Pythagorean Theorem:

a^2 + b^2 = c^2

a^2 + 21^2 = 42^2

a^2 + 441 = 1764

a^2 = 1764 - 441

a^2 = 1323

a = 36.37 cm

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