Higher November 2020 Paper 2R Q9
9
(a) Factorise \(\;x^2 - x - 42\) (2)
(b) Solve the inequality \(\;3x + 15 \lt 8x + 3\)
Show clear algebraic working. (3)
Show clear algebraic working. (3)
| Scheme | Marks |
|---|---|
| M1 | |
| \((x + 6)(x - 7)\) | A1 |
| (2) |
Notes
M1: for \((x \pm 6)(x \pm 7)\)
A1: for \((x + 6)(x - 7)\) or \((x - 7)(x + 6)\)
isw roots given if candidate solves the quadratic = 0
| Scheme | Marks |
|---|---|
| \(3x - 8x \lt 3 - 15\) or \(15 - 3 \lt 8x - 3x\) | M1 |
| \(-5x \lt -12\) or \(12 \lt 5x\) | M1 |
| \(x \gt 2.4\) | A1 |
| (3) | |
| (5 marks) |
Notes
M1: accept as equation or with the wrong inequality sign.
M1: accept as equation or with the wrong inequality sign.
A1: Accept \(2.4 \lt x\) or \(x \gt \dfrac{12}{5}\) oe
allow (−∞, 2.4)
award M1 M1 A0 for 2.4 with = sign or no inequality or incorrect inequality sign.