Find the length of the third side. If necessary, round to the nearest tenth.
12
5

9514 1404 393

  13

Step-by-step explanation:

The hypotenuse can be found using the Pythagorean theorem. If we call that side 'c', then the theorem tells us ...

  c² = 5² + 12²

  c² = 25 +144 = 169

  c = √169 = 13

The length of the third side is 13 units.

Additional comment

The numbers (5, 12, 13) are what is called a "Pythagorean triple." That is, they are integers that can be used to form a right triangle. Others often seen in algebra problems are the (3, 4, 5), (7, 24, 25), and (8, 15, 17) triples. It can be worth your trouble to remember these. Then when you see side lengths of 5 and 12, you don't need to do any math to know the third side is 13.

square pyramid

step-by-step explanation:

square prism looks like nothing like that

triangular prism has a rectangular base instead of a square base

tetrahedron has a triangular base