Higher November 2022 Paper 1 Q14
14 Craig wants to draw a graph, for values of \(x\) from \(-3\) to 3,
where the \(x\)-coordinate and \(y\)-coordinate are always in the ratio \(\quad 2 : 1\)
Here is his graph.

Make two criticisms of Craig’s graph. [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| Explanation that the ratio and graph do not match | B1 | eg This is the graph of \(y = 2x\), not \(y = \dfrac{1}{2}x\) This is the graph of \(x : y = 1 : 2\) It should go through (3, 1.5) |
| Explanation that the domain of the graph is incorrect | B1 | eg The graph goes from \(x = 0\), not \(x = -3\) |
Additional guidance
| 3 : 6 is 1 : 2 | B1 |
| (3, 6) doesn’t work | B1 |
| The gradient is 2, not \(\dfrac{1}{2}\) | B1 |
| He got \(x\) and \(y\) mixed up | B1 |
| His graph is not going up in the ratio 2 : 1 | B0 |
| The gradient is 2 | B0 |
| He didn’t follow the ratio | B0 |
| The graph doesn’t have negative numbers | B1 |
| There are no minuses | B1 |
| It doesn’t go from \(-3\) to 3 | B1 |
| The axes should be the same length | B0 |