I think it's 3,3 because 2,2 are on the left 6,71 are on the right and median is the middle.
Rewrite the equation as
If we choose , the right hand side becomes zero, and so does the left hand side.
If you graph the two functions and , you'll see that there are only two solutions, so the ones we found are the only ones.
The answer you are looking for is 0.696, rounded to 0.7
A pythagorean theorem must satisfy a² + b² = c²
16² + 20² = 25²
256 + 400 = 625
656 ≠ 625 so no, the set 16, 20, 25 does not represent a pythagorean triple