4400 Higher June 2006 Paper 4 Q8
8
(a) Solve \(\quad 3(x + 4) = 27\) (3)
(b) Solve \(\quad y^2 - 2y - 120 = 0\) (3)
| Scheme | Marks |
|---|---|
| \(3x + 12 = 27\) | M1 |
| \(3x = 15\) | A1 |
| 5 | A1 |
| (3) |
Notes
A1: \(x + 4 = 9\): M1A1
| Scheme | Marks |
|---|---|
| \((y - 12)(y + 10)\) or \(\dfrac{2 \pm \sqrt{(-2)^2 - 4 \times (-120)}}{2}\) | M1 |
| \(y = 12\) or −10 | A1 A1 |
| (3) | |
| (6 marks) |
Notes
M1: allow \((y \pm 12)(y \pm 10)\) correct subst’n
A1A1: NB corr ans from inc wking: A0A0
T & I: 3mks or 0 mks