Higher November 2022 Unit 1 Q5
5. The diagram below shows the graph of a straight line for values of \(x\) from –1 to 3.
(a)
(i) Write down the gradient of the line above. [1]
(ii) Write down the equation of the line in the form \(y = mx + c\). [2]
(b) Show that the lines
\(y = 3x - 8\) and \(2y - 6x = 23\)
are parallel to each other. [2](a)(i)
| Scheme | Marks | Comments |
|---|---|---|
| 4 | B1 | Accept 4/1 or equivalent. The correct gradient has to be unambiguously shown. \(y = 4x - 2\) is B0, but \(y =\)4\(x - 2\) is B1. Award B0 for a final answer of \(4x\). |
(a)(ii)
| Scheme | Marks | Comments |
|---|---|---|
| \(y = 4x - 2\) | B2 | FT ‘their gradient’ from (a) Award B1 for one of the following:
|
| Scheme | Marks | Comments |
|---|---|---|
| Valid explanation with rearranged equation AND indicating that the gradient is 3 or equivalent e.g. “2y – \(6x = 23\) is the same as \(y = 3x + 11{\cdot}5\), so the gradient of both lines is 3” “\(2y = 6x + 23\) and \(2y = 6x - 16\) and the gradient of both lines is 3” | B2 | B1 for one of the following:
Do not allow:
|