Answer: Yes, the side lengths will form a Pythagorean triple.
Step-by-step explanation: We are given that triangle ABC has side lengths 3, 4 and 5 units.
We are to check whether the side lengths form a Pythagorean triple.
The Pythagorean triple is
Hypotenuse² = Perpendicular² + Base².
Now, for the given triangle ABC, let AB = 3 units, BC = 4 units and CA = 5 units.
Then, we have

Therefore, we get

Thus, the side lengths will form a Pythagorean triple with side CA as the hypotenuse.