I'm not sure, but what I got was -8.5, since it is only stating that it is -17 and 5, and you need to figure out Point B, when it is between A and 0. So, you don't pay attention to 1-5. You only want -17 through 0. -17 divided by two would be -8.5
In a 45 · 45 · 90 triangle, the hypotenuse is √2 · legs, because a 45 · 45 · 90 triangle is isosceles, so the legs are the same length. So, we have 3√2 · √2 = 6, so the hypotenuse is 6.
