a salesman who's always looking for an 'angle' [=looking for a way to convince people to buy the things he is selling]
The two lines meet at a 30-degree 'angle' to each other. = There is a 30-degree 'angle' between the two lines.
The two lines form a sharp 'angle'. = The two lines meet/intersect at a sharp 'angle' (to each other).
(..) I know you're looking at the obvious suspects, convicted felons, child molesters. And I understand why, but, Len, I think you're coming at it from the wrong angle. - Honey... - Herman Stolfuz just across the street. Now, he appears to be perfectly normal, but, Len, - the man wears adult diapers. (..)2009 The Lovely Bones