Hopefully, you recognized that 3 and 5 are part of the 3-4-5 Pythagorean triplet. If you did, then you would automatically know that 4 is a possible value for the third side. If not, you could have solved using the Pythagorean Theorem, using 5 or the unknown side as the hypotenuse.
If you used 5 as the hypotenuse, then you would have gotten the length of the third side as 4.
| If you used 3 and 5 as the legs, then you would have gotten |
|
c2
|
= |
32
|
+ |
52
|
, or |
c2
|
= |
9 |
+ |
25 |
= |
34. |
The square root of 34 is approximately 5.83, so this is another possible length of the third side.
