Similarity and congruence
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problemAnamorphic art is used to create intriguing illusions - can you work out how it is done? -
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problemFrom All Corners
Straight lines are drawn from each corner of a square to the mid points of the opposite sides. Express the area of the octagon that is formed at the centre as a fraction of the area of the square.
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problemPoints in Pairs
Move the point P to see how P' moves. Then use your insights to calculate a missing length.
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problemWedge on Wedge
Two right-angled triangles are connected together as part of a structure. An object is dropped from the top of the green triangle where does it pass the base of the blue triangle?
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problemPentakite
Given a regular pentagon, can you find the distance between two non-adjacent vertices?
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problemStadium Sightline
How would you design the tiering of seats in a stadium so that all spectators have a good view?
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problemPent
The diagram shows a regular pentagon with sides of unit length. Find all the angles in the diagram. Prove that the quadrilateral shown in red is a rhombus.
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problemChord
Equal touching circles have centres on a line. From a point of this line on a circle, a tangent is drawn to the farthest circle. Find the lengths of chords where the line cuts the other circles.
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problemAnother Triangle in a Triangle
Can you work out the fraction of the original triangle that is covered by the green triangle?