3-(-5)=8
6-(-1)=7
Use the Pythagorean Theorem, 8²+7²=a²
64+49=a²
113=a²
a=√113
But I don't think is the distance, this is your answer.
(3, -1) (-5, 6)
Bring it to the expression, y=mx+b
3m+b=-1
-5m+b=6
m=-7/8
b=13/8
the final expression is y=-7/8x=13/8