if PQ=21 cm and QR=5cm, then what are the possible lengths for PR so that line PQ, line QR, and line PR can form a triangle? explain your reasoning
I have a pretty good idea what the answer is i just need it explained a smidge more.
We know that PQ is 21 cm and QR is 5 cm. There are only 2 possible answer for this and you use only one formula. It's called the Pythagorean theorem.
The first possible is this. If the hypotenuse(the longest side of a triangle) is PR, we do: a² + b² = c² ←Fill in the numbers 21² + 5² = c² 441 + 25 = c² 466 = c² √466 = 21.12 cm←Possible length
The second possible is this: 5² + b² = 21² 25 + b² = 441 b² = 441 - 25 b² = 416 √416 = 20.4←Another possible answer
