False position method lines on a conic section. A more typical example is this "joint purchase" problem: Now an item is purchased jointly; everyone contributes 8 [coins], the excess is 3; everyone contributes 7, the deficit is 4. Tell: The number of people, the item price, what is each? Answer: 7 people, item price 53. Between the 9th and 10th centuries, the Egyptian mathematician Abu Kamil wrote a now-lost treatise on the use of double false position, known as the "Book of the Two Errors" ("Kitāb al-khaṭāʾayn"). The oldest surviving writing on double false position from the Middle East is that of Qusta
Midfielder mark specific opposition attackers. Defensive midfielders may also move to the full-back or centre-back positions if those players move forward to join in an attack. Sergio Busquets described his attitude: "The coach knows that I am an obedient player who likes to help out and if I have to run to the wing to cover someone's position, great." A good defensive midfielder needs good positional awareness, anticipation of opponent's play, marking, tackling, interceptions, passing and great stamina and strength (for their tackling). A holding or deep-lying midfielder stays close to their team's defence, while other midfielders may move forward to