Subject: pythagorean theorem

Name: lauren fitzgerald
Who is asking: Student
Level: All

Question: how do you find the length of th hipotnuse( or however you spell that word). i understand you have to add the two sides. but when i do add i always end up with this way off answer. i donot understand at all . please help me.

lauren fitzgerald
white station middle school( honors program) memphis tennesse

Hi Lauren,

To find the length of the hypoteneus in a right angle triangle, use the pythagorean theorem: c2 = a2 + b2 where c is the hypoteneus and a,b are the other two sides. You said you were "adding the other two sides". In fact, you must square the other two sides first, and then add. The length of the hypoteneus is then the square root of this sum.

For example, suppose the other two sides are 3 and 4
c2  =  a2 + b2
 =32 + 42
 =9 + 16
 =25

c squared is 25 so we need a number such that, when you square it, you get 25. 52 = 25 so c = 5

Thus, the length of the hypoteneus is 5.

Cheers,
Paul
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