Shape and Space Problems Year 9           

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Examples Page Ref  Problem Title Objectives Ref Description Key Words
169, 183, 193 Paper Folding Similarity, Gradients A square is simply folded over and then opened out - what does the crease look like ? Similar, Slope, Gradient
185, 188, 209 Overlapping Figures Angles, Symmetry, Similar triangles How much overlap between 2 congruent regular polygons ?  Congruent, Corresponding, Interior angle, Isometric
185 P Where You Like Properties of Triangles Prove that the sum of distances from any point in an equilateral triangle to the sides is constant Proof, Triangle
 185, 187 L-Shape Area, Proof How to divide any 2-rectangle 'composite' in half?  Symmetry, Proof, Bisect
123, 185, 247 Overlapping Squares 2 2-D Shape, Proof, Trigonometry, Surds Rotate 2 squares - how much of the lower one can you see? Simple to state, scope to explore...  Congruent, Symmetry, Pythagoras, Surds, Proof
187, 199 A Conic Journey Pythagoras, 2-D and 3-D Shape  Find the shortest route across a rather special cone. Pythagoras, Cross-section, Chord
91, 127, 189 The Magic of Pythagoras Pythagoras This Problem is a variation on the Well in the Courtyard problem... and has a lovely, surprising answer as unwanted terms 'cancel out' !  Pythagoras, Subject of the formula
127, 189 Truncated Square Pythagoras Another 'not-enough-information-surely?' problem that comes out nicely when Pythagoras is liberally applied ...  Pythagoras, Subject of the formula
189 Double Squares Pythagoras A surprisingly simple trick to writing numbers as the sums of squares - a must-see ! Pythagoras
189, 219 Quickest Route Co-ordinate distances, Pythagoras Jeeves needs to escape across a swimming pool - but what's his quickest escape route ? Pythagoras
191, 193, 217 Triangle Dissections Congruence, Similarity, Enlargement A series of puzzles concerned with dissecting equilateral triangles into smaller parts Congruent, Similar
191 The Radius Congruence, Similarity A simple application of Similar triangles Congruent, Similar
 193,61, 81, 215 Pendants Similarity, Enlargement 'Area Factors' under enlargement give quick answers to this problem Similar, Enlargement, Scale factor 
193, 215, 234 Sculpt Big Ratio, Enlargement, Similarity, Cylinders A sculptor chooses between similar large and small designs, in order to maximize profits... Scale factor, Volume, Enlarge, Proportional 
193, 235, 237 Shortest Half 2-D Shape, Dynamic Geometry What is the most efficient way to divide an equilateral triangle into two equal areas ? Arcs, Sectors, Scale Factor
200, 207 TetraCubes 3D Shape Identify shapes, then use to build mini Soma Cubes Plan, View, Symmetry
201 Sliced Cube 3-D Shape,  Pythagoras Visualize, then prove, a result about a bisected cube. Cross-Section, Plane, Properties
161, 165, 203 Graphic Convergence Co-ordinates, Mappings, Combination of Transformations A pair of mappings for x and y lead to a convergent sequence of points, which can also be viewed as a combination of transformations - quite pretty. Map, Invariant
213 Square in a Triangle Transformations, Symmetries How to squeeze the largest possible square inside any triangle? Enlargement
215, 221 Forensic Triangles Constructions, Dynamic Geometry Reconstruct the original triangle from the sides' mid-points  Medians, Similar, Parallel
219 Points In Between Co-ordinates Finding mid-points and points of trisection, using 'weighted average' co-ordinates, and hence finding the 'centroid' Co-ordinates, Line, Mid-point, Average, Graphs
221 Eggs Constructions, Compasses First take an egg... Compasses, Perpendicular, Arc, Tangent
221 Triangle in a Square Constructions, Dynamic Geometry How to squeeze the largest possible equilateral triangle inside a square? Compasses, Rotation
223, 245 Height of the Tower Similar Triangles, Scale Drawing There's a tower, see, across this river, and what you've got to do is...  Similarity, Elevation
133, 227  Overlapping Squares 1 Loci, Graphs, 2-D shape This problem offers an element of surprise in that the locus of possible solutions isnít the straight line that pupils may well expect Region, Proof, Locus 
81, 91, 233 Average Speed Speed, Ratio + Proportionality A nice introduction to ratio methods for combining average speeds over 2 sections of a journey Speed, Average
91, 233 A Walk In The Bush Fractions, Measurements An 'average speed' problem that comes out very sweetly - involving some up and down hills Speed, Average
235 How Deep Is The Well Circles Fairly straightforward circumference calculations Pi, Circumference
237 Pie Free Circles Circles, Area A section of a circle turns out to have an area independent of Pi Pi, Arc, Pythagoras
237 Snake Eyes Circles, Pythagoras A circular area that turns out not to involve Pi !  Pi, Hypotenuse, Pythagoras
237 Target Practice Circles The middle ring of a circular target has a simple area... Pi, Proportion
237 Loo Roll Emergency Circles When the loo roll looks half-size, how much is really left? Pi, Circle, Area
35, 237  Wiggly Paths Circles Surprisingly pretty result about the area of winding pathways...(cf P.35 Garden Path)  Pi, Radius, Arc
237 Square Peg, Round Hole Circles Which fits better-a square peg in a round hole, or a round peg in a...? Pi
155, 237 Pick A Shape Generate sequence, Find nth term Pick's Theorem for Areas on a dotty grid Formula, Generate Tn, Proof
 

 

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Last modified: June 18, 2007