4MA0 Higher June 2011 Paper 3 Q3
3
(a) Factorise \(w^2 - 9w\). (2)
(b) Solve \(5x - 1 = 2x - 7\) (3)
(c) Expand and simplify \((y - 7)(y + 3)\). (2)
| Scheme | Marks |
|---|---|
| \(w(w - 9)\) | B2 |
| (2) |
Notes
B2: Award B2 also for \((w \pm 0)(w - 9)\)
B1 for factors which, when expanded & simplified, give two terms, one of which is correct except B0 for \((w + 3)(w - 3)\)
SC B1 for \(w(w - 9w)\)
| Scheme | Marks |
|---|---|
| \(3x = -6\) or \(3x = 1 - 7\) or \(5x - 2x = -6\) oe | M2 |
| −2 | A1 |
| (3) |
Notes
M2: for correct rearrangement with \(x\) terms on one side and numbers on the other AND correct collection of terms on at least one side
M1 for \(5x - 2x = 1 - 7\) oe
ie correct rearrangement with \(x\) terms on one side and numbers on the other
A1: cao dep on M2
| Scheme | Marks |
|---|---|
| \(y^2 + 3y - 7y - 21\) | M1 |
| \(y^2 - 4y - 21\) | A1 |
| (2) | |
| (Total 7 marks) |
Notes
M1: for 3 correct terms out of 4
or for 4 correct terms ignoring signs
or for \(y^2 - 4y + n\) for any non-zero value of \(n\)
A1: cao