<> <> Quadratic: DEFINITIONS = BEGIN Roots: TYPE = RECORD [nRoots: [0..2], r1, r2:REAL]; -- r1 <= r2 if nRoots=2. RealRoots: PROCEDURE [a,b,c:REAL] RETURNS [Roots]; -- solves axx + bx + c = 0, real roots only. END.