4MA0 Higher January 2015 Paper 3R Q4
4
(a) Factorise \(6w + 15\) (1)
(b) Expand and simplify \((x + 4)(x + 7)\) (2)
(c) Solve \(3(x - 5) = 7x + 12\)
Show clear algebraic working. (3)
Show clear algebraic working. (3)
| Scheme | Marks |
|---|---|
| \(3(2w + 5)\) | B1 |
| (1) |
| Scheme | Marks |
|---|---|
| \(x^2 + 4x + 7x + 28\) | M1 |
| \(x^2 + 11x + 28\) | A1 |
| (2) |
Notes
M1: for 3 correct terms out of 4 or for 4 correct terms ignoring signs
or for \(x^2 + 11x + c\) for any non-zero value of \(c\)
or for \(\ldots + 11x + 28\)
| Scheme | Marks |
|---|---|
| \(3(x - 5) = 3x - 15\) | M1 |
| \(3x - 15 = 7x + 12\) \(-15 - 12 = 7x - 3x\) or \(3x - 7x = 12 + 15\) oe | M1 |
| −6.75 | A1 |
| (3) | |
| (6 marks) |
Notes
M1: For correct expansion of bracket (seen anywhere)
M1: correct rearrangement with \(x\) terms on one side and numbers on the other side
\(-15 - 12 = 7x - 3x\) or
\(3x - 7x = 12 + 15\) or better
A1: Award 3 marks if M1 scored and answer correct, accept − 6.75 oe