June 2018 Paper 2 Q5
5 On the grid, draw the graph of \(\quad y = \mathrm{f}(x)\)
\[\begin{aligned} \mathrm{f}(x) &= x + 4 &\qquad& -4 \leqslant x \lt 0 \\ &= 4 - 3x && 0 \leqslant x \lt 2 \\ &= -2 && 2 \leqslant x \leqslant 5 \end{aligned}\][4 marks]
| Answer | Mark | Comments |
|---|---|---|
| Line from \((-4,\ 0)\) to \((0,\ 4)\) | M1 | mark intention |
| Line from \((0,\ 4)\) to \((2,\ -2)\) | M1 | lines do not have to be straight but must pass through all integer points |
| Line from \((2,\ -2)\) to \((5,\ -2)\) | M1 | only condone the first instance of a line that extends beyond the given domain |
| Straight line from \((-4,\ 0)\) to \((0,\ 4)\) and straight line from \((0,\ 4)\) to \((2,\ -2)\) and straight line from \((2,\ -2)\) to \((5,\ -2)\) | A1 | all straight lines must be the correct length with no other lines graph must be accurate SC3 \((-4,\ 0)\) and \((-3,\ 1)\) and \((-2,\ 2)\) and \((-1,\ 3)\) and \((0,\ 4)\) and \((1,\ 1)\) and \((2,\ -2)\) and \((3,\ -2)\) and \((4,\ -2)\) and \((5,\ -2)\) plotted (any other points plotted must be correct ones for the graph) SC2 \((-4,\ 0)\) and \((0,\ 4)\) and \((2,\ -2)\) and \((5,\ -2)\) plotted (any other points plotted must be correct ones for the graph) |
Additional guidance
 | M3A1 |
| Dashed or dotted lines can score up to M3A0 | |
| Points may be implied by a correct line | |
| M mark examples eg1 2 correct lines and 1 extended line (but otherwise correct) eg2 1 correct line and 2 extended lines (but otherwise correct) eg3 3 extended lines (but otherwise correct) | M3A0 M2A0 M1A0 |