4MA0 Higher January 2015 Paper 3 Q10
10
(a) Find the gradient of the line with equation \(3y - 2x = 6\) (2)
(b) Find an equation of the line with gradient –3 that passes through the point (2, 5). (2)
| Scheme | Marks |
|---|---|
\(y = \dfrac{2x + 6}{3}\) or \(y = \dfrac{2}{3}x + 2\) e.g. \(\dfrac{4 - 2}{3 - 0}\) | M1 |
| \(\dfrac{2}{3}\) | A1 |
| (2) |
Notes
M1: For a correct equation with y the subject or \(\dfrac{\text{diff of } y \text{ values}}{\text{diff of } x \text{ values}}\) for any two correct points on the line.
Allow 0.666(66666....) rounded or truncated to at least 3SF instead of \(\dfrac{2}{3}\)
A1: Allow M1A1 if \(\dfrac{2}{3}\) follows an equation with an incorrect constant.
Eg \(y = \frac{2}{3}x + 3\) followed by an answer of \(\dfrac{2}{3}\)
M1A0 for \(\frac{2}{3}x + 2\) or \(\frac{2}{3}x\)
Allow 0.666(66666....) rounded or truncated to at least 3SF instead of \(\dfrac{2}{3}\)
| Scheme | Marks |
|---|---|
| \(5 = -3 \times 2 + c\) or \(c = 5 + 3 \times 2\) | M1 |
| \(y = -3x + 11\) | A1 |
| (2) | |
| (4 marks) |
Notes
A1: Allow ISW
oe [e.g. \(y - 5 = -3(x - 2)\)]