Find the distance between the following pair of points:
(i) (-6,7) and (-1,-5)
(ii) (a+b,b+c) and (a-b,c-b)
(iii) (a sin α,−b cos α) and (−a cos α,b sin α)
(iv) (a,0) and (0,b)
Find the distance between the points (i) P(-6, 7) and Q(-1, -5) (ii) R(a + b, a - b) and S(a - b, - a - b)