Higher January 2019 Paper 2 Q21
21 Line L has equation \(4y - 6x = 33\)
Line M goes through the point \(A\ (5, 6)\) and the point \(B\ (-4, k)\)
L is perpendicular to M.
Work out the value of \(k\).
(4)
| Scheme | Marks |
|---|---|
| \(y = \dfrac{6}{4}x\ (+33)\) or (gradient =) \(\dfrac{6}{4}\) oe | M1 |
| \(m \times \dfrac{6}{4} = -1\) or (gradient of M =) \(-\dfrac{2}{3}\) oe | M1 |
| \(\dfrac{k - 6}{-4 - 5} = \text{``}{-\dfrac{2}{3}}\text{''}\) | M1 dep |
| 12 | A1 |
| (4) | |
| (4 marks) |
Notes
M1 dep: or complete method to find equation of line (\(3y = -2x + 28\)) and then substitution of \(x = -4\)