Higher November 2016 Unit 1 Q6
6. In this question you will be assessed on the quality of your organisation, communication and accuracy in writing.
Each side of a square is of length \((2x + 3y)\) cm.
The perimeter of the square is 62 cm.
Each side of a regular octagon is of length \((x + 2y)\) cm.
The perimeter of the octagon is 72 cm.
Use an algebraic method to find the value of \(x\) and the value of \(y\). [5 + 2 OCW]
\(x\) = …………………… \(y\) = ……………………
| Scheme | Marks | Comments |
|---|---|---|
| (Perimeter of square =) \(4 \times (2x + 3y) = 62\) | B1 | Sight of \(8x + 12y = 62\) or equivalent e.g. \(2x + 3y = 15{\cdot}5\) |
| (Perimeter of octagon =) \(8 \times (x + 2y) = 72\) | B1 | Sight of \(8x + 16y = 72\) or equivalent e.g. \(x + 2y = 9\) |
| Correct method to solve simultaneous equations, as far as attempt at subtraction | M1 | F.T. ‘their equations’. Allow 1 ‘slip’, if multiplication used, but not in ‘equated variable’ for M1 only. |
| \(y = 2{\cdot}5\) | A1 | |
| \(x = 4\) | A1 | F.T. from their 1st variable. (Substitution in any relevant equation.) |
| Organisation and Communication. | OC1 | For OC1, candidates will be expected to:
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| Accuracy of writing. | W1 | For W1, candidates will be expected to:
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