Foundation November 2019 Paper 2 Q18
18 Solve by factorising.
\[x^2 + 9x + 20 = 0\][3]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| \((x + 4)(x + 5)\) | M2 | M2 for \((x + 4)\) and \((x + 5)\) or M1 for \((x + a)\) and \((x + b)\) where \(ab = 20\) or \(a + b = 9\) or \(x(x + 4) + 5(x + 4)\) or \(x(x + 5) + 4(x + 5)\) If M0 scored SC1 for \(x + 4 = 0\) and \(x + 5 = 0\) | For M2 or M1 condone omission of final bracket |
| \({}^{-}5\) and \({}^{-}4\) nfww | B1 | STRICT FT their factors dep on two brackets in factors. If 0 scored SC1 for answers \(\pm 5\) and \(\pm 4\) | |