South Australia contains 324 separate Protected Areas with a total land area of 21,630,995 hectares(21.97% of the state’s area). 18 of these are National parks, totalling 4,337,430 hectares (4.41% of the state’s area).
... trinomial of the form x2 + 2xy + y2. Since "2xy" in this case is (b/a)x, we must have y = b/(2a), so we add the square of b/(2a) to both sides, ...