Hey Asthuran00.

I wouldn't worry too much about the interpretation: you answered what they asked for and that's what is important here.

Also for question a) you should probably write the line in terms of t where t = 1 corresponds to (5,5) and t = -1 corresponds to (-7,-1) and then show that t = 0 corresponds to (0,0).

Keep in mind that your answer is right, but when you asked for the bisector it's a good idea if you have some evidence that the point does divide the line into two equal parts.