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).
(..) and I wasn't checked for powder traces, Mr, Greenspan, if I put a gun to your head and then turn and shoot your wife, how could the bullet travel at an upward angle? Objection! Mr, Greenspan is not an expert in ballistics, Sustained, Mr, Locket, if you continue in this line, (..)1994 The Glass Shield
(..) I loved my wife, You testified that on September , Teddy Woods shot your wife from your side of the car, How is it, sir, that the bullet traveled from a lower angle? He would've had to have been on his knees with the car door open - for that to happen, - I don't know,,, I am not done with (..)1994 The Glass Shield