2+3+5=180
the the angles are: 2/10 of 180=36
3/10 of 180=54
5/10 of 180=90
yes, it is a right triangle.
If u and v are indeed vectors,

,
Should would have ran 8.6 KM
The easiest way is to plug x=-4, y=-1 in the equation to see which one works.
8(-4)-9(-1)=-23
B is correct.