Foundation November 2020 Paper 1 Q18
18 A triangle has sides of length 14.1 cm, 14.8 cm and 19.5 cm.
Is this a right-angled triangle?
Show how you decide.
.................. because .................. [4]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| No, with full correct working and a statement referring to correct comparable values | 4 | M3 for \(\sqrt{14.1^2 + 14.8^2} = 20.4\) to 20.5 or \(14.1^2 + 14.8^2 = 417.8\) to 417.9 and \(19.5^2 = 380.2\) to 380.3 OR M2 for \(\sqrt{14.1^2 + 14.8^2}\) or \(14.1^2 + 14.8^2\) and \(19.5^2\) OR M1 for \(14.1^2 + 14.8^2\) If 0 scored, SC2 for 20.4 to 20.5 or 12.6 to 12.7 or 13.4 to 13.5 with no or insufficient working or SC1 for 417.8 - 417.9 or 161.2 - 161.21 or 181.4 to 181.44 with no or insufficient working | Do not accept a scale drawing method Need No and a comment for 4 marks Need to see evidence Accept equivalent alternative methods e.g. using subtraction: M3 for \(\sqrt{19.5^2 - 14.8^2} = 12.6\) to 12.7 OR M2 for \(\sqrt{19.5^2 - 14.8^2}\) OR M1 for \(19.5^2 - 14.8^2\) |