4MA0 Higher January 2014 Paper 3 Q11
11 Solve \[\dfrac{6x - 1}{4} - \dfrac{5 - 2x}{2} = 1\]
Show clear algebraic working.
(4)
| Scheme | Marks |
|---|---|
Eg. \(\dfrac{4(6x - 1)}{4} - \dfrac{4(5 - 2x)}{2} = 1 \times 4\) or \(6x - 1 - 2(5 - 2x) = 4\) or \(\dfrac{6x - 1 - 2(5 - 2x)}{4}\;(= 1)\) or \(\dfrac{6x - 1}{4} - \dfrac{2(5 - 2x)}{4}\;(= 1)\) or \(1.5x - 0.25 - (2.5 - x) = 1\) | M1 |
Eg. \(6x - 1 - 10 + 4x\;(= 4)\) or \(\dfrac{6x - 1 - 10 + 4x}{4}\;(= 1)\) or \(1.5x - 0.25 - 2.5 + x\;(= 1)\) | B1 |
| Eg. \(10x = 15\) or \(10x - 11 = 4\) or \(10x - 1 - 10 = 4\) or \(6x + 4x - 11 = 4\) or \(10x - 15 = 0\) | B1 |
| 1½ oe | A1 |
| (4) | |
| (4 marks) |
Notes
M1: for clear intention to multiply all terms by 4 or a multiple of 4
or to express LHS as a single fraction with a denominator of 4 or a multiple of 4
or to express LHS as the sum of two fractions with denominators of 4 or a multiple of 4
May be implied by first B1
B1: Expanding brackets
B1: for correct rearrangement of a correct equation with terms in \(x\) isolated
A1: Award full marks for a correct answer if at least M1 scored.
The mark scheme states that for this question the correct answer alone does not imply a correct method.