Researched and devised by Oliphant Jackson[?], MRCVS, the Jackson Ratio is a method of determining whether a tortoise, or a member of another chelonia species, is maintaining its optimum bodyweight, which is necessary for a successful hibernation
... is positive, then there are two different solutions x, both of which are real. (Geometrically, this means that the parabola intersects the x-axis in two points.)
If ...