Step-by-step explanation:
Pythagoras : the lengths are the hypotenuses of the right-angled triangles created by the differences of the x and the y coordinates.
so,
AB² = (0 - -3)² + (2 - 8)² = 3² + (-6)² = 9 + 36 = 45
AB = sqrt(45) ≈ 6.7
CD² = (-2 - 0)² + (2 - -4)² = (-2)² + 6² = 4 + 36 = 40
CD = sqrt(40) ≈ 6.3
The first one YES and the last one NO!