Question 1

How do I find a leg if I know the hypotenuse?

Accepted Answer

Rearrange: b = √(c² − a²). With c = 13 and a = 5, b = √144 = 12.

Question 2

How do I calculate a TV screen's diagonal?

Accepted Answer

The width and height are the legs; a 16:9 screen 120 cm wide is about 67.5 cm tall, so the diagonal is about 137.7 cm.

Question 3

Does the theorem work in three dimensions?

Accepted Answer

Yes. A box's space diagonal is √(a² + b² + c²).

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