Alice and Bob want to get from one corner of this rectangular field to the other. Alice walks round the edge of the field. Bob cuts right across. How much further did Alice walk? Pythagoras’ Theorem – Exercise 1 1. Find the side marked with the letter (you do not need to copy the diagrams). 3. [Kangaroo Pink 2008 Q3] Four unit squares are placed edge to edge as shown. What is the length of the line ππ? ο 2. To rescue a cat I put a ladder of length 10m against a tree, with the foot of the latter 2.5m away from the tree. How high up the tree is the cat? Pythagoras’ Theorem – Exercise 1 1. Find the side marked with the letter (you do not need to copy the diagrams). [Based on JMO 1996 A6] The length of the shortest diagonal of an octagon is 1. What is the length of the longest diagonal? 3. Alice and Bob want to get from one corner of this rectangular field to the other. Alice walks round the edge of the field. Bob cuts right across. How much further did Alice walk? 4. [Kangaroo Pink 2008 Q3] Four unit squares are placed edge to edge as shown. What is the length of the line ππ? 2. To rescue a cat I put a ladder of length 10m against a tree, with the foot of the latter 2.5m away from the tree. How high up the tree is the cat? www.drfrostmaths.com 5. [Based on JMO 1996 A6] The length of the shortest diagonal of an octagon is 1. What is the length of the longest diagonal? Pythagoras’ Theorem – Exercise 2 5. (a) What is the height of an equilateral triangle with side length 6? Give your answer in exact form unless otherwise specified. 1. Determine π₯. (b) What is its area? 6. Determine π§. 2. Determine π¦. 7. Find the height of this isosceles triangle. 8. Find the area of this isosceles triangle. 3. Santa Claus and Rudolph are sitting at the corner of a square swimming pool of 10m by 10m, which has frozen over. The want to get to the other corner of the pool, where Mary Christmas has left some brandy and a carrot. Rudolph runs around the edge of the pool, while Santa, who has recently been on a diet, decides to risk walking diagonally across the ice. Calculate the distance saving, to 2 decimal places. 4. Two snowmen are back to back, facing in opposite directions. They each walk 3km forward, turn left and then work a further 4km. How far are the snowmen from each other? www.drfrostmaths.com 9. Determine π₯. 10. [IMC 2008 Q20] What, in cm2, is the area of this quadrilateral? 11. [IMC 2009 Q20] A square, of side two units, is folded in half to form a triangle. A second fold is made, parallel to the first, so that the apex of this triangle folds onto a point on its base, thereby forming an isosceles trapezium. What is the perimeter of this trapezium? A 4 + √2 B 4 + 2√2 C 3 + 2√2 D 2 + 3√2 E 5 12. Determine π₯ (using an algebraic method). ο Killer 3: [JMO 2007 B5] A window is constructed of six identical panes of glass. Each pane is a pentagon with two adjacent sides of length two units. The other three sides of each pentagon, which are on the perimeter of the window, form half of the boundary of a regular hexagon. Calculate the exact area of the glass in the window. ο Killer 4: [JMO Mentoring May2012 Q4] A triangle has two angles which measure 30° and 105°. The side between these angles has length 2 cm. What is the perimeter of the triangle? (Hint: split the triangle somehow?) ο Killer 5: Determine π₯ (using an algebraic method). ο Killer 1: [JMO 2006 B4] Start with an equilateral triangle π΄π΅πΆ of side 2 units, and construct three outwardpointing squares ABPQ, BCTU, CARS and the three sides AB, BC, CA. What is the area of the hexagon PQRSTU? ο Killer 2: [JMO 1999 B4] The regular hexagon π΄π΅πΆπ·πΈπΉ has sides of length 2. The point π is the midpoint of π΄π΅. π is the midpoint of π΅πΆ and so on. Find the area of the hexagon πππ πππ. www.drfrostmaths.com ο Killer 6: Determine π₯.