line_line
Intersection of the line through x,y and p,q and the line through a,b and u,v, OR
of the line through x,y with direction d1 and the line through a,b and direction d2
If you have to put a coefficient using some other function symbol (for example √2; π/2), put it in a numerical form
(1.414213562373095, 1.5707963267949), for example using this (or this)