geometry question on how to find value x

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by papgust » Wed Mar 17, 2010 9:35 pm
Yes, you can use pythagorean theorem.

We have a right angle and we have 2 of the pythagorean triplets (x,12,13) and (3,4,x) [where x is 5].

Leftmost triangle forms a right triangle. The other angle is 5 [3-4-5 triangle]
Rightmost triangle forms another right triangle. The other angle is 5 [5-12-13 triangle]. The opposite angle to side '5' of 5-12-13 triangle is 55 degrees.

The opp angle to side '5' of 3-4-5 triangle is also 55 degrees.

So, x is 180 - (55+55) = 70.

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by [email protected] » Wed Mar 17, 2010 9:42 pm
papgust wrote:Yes, you can use pythagorean theorem.

We have a right angle and we have 2 of the pythagorean triplets (x,12,13) and (3,4,x) [where x is 5].

Leftmost triangle forms a right triangle. The other angle is 5 [3-4-5 triangle]
Rightmost triangle forms another right triangle. The other angle is 5 [5-12-13 triangle]. The opposite angle to side '5' of 5-12-13 triangle is 55 degrees.

The opp angle to side '5' of 3-4-5 triangle is also 55 degrees.

So, x is 180 - (55+55) = 70.
I had no clue that the 5-12-13 triangle existed. thanks papgust.
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