Quadrilaterals

There are 65 NRICH Mathematical resources connected to Quadrilaterals
Dividing the Field
problem

Dividing the field

Age
14 to 16
Challenge level
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A farmer has a field which is the shape of a trapezium as illustrated below. To increase his profits he wishes to grow two different crops. To do this he would like to divide the field into two trapeziums each of equal area. How could he do this?
Fred the Class Robot
problem

Fred the class robot

Age
7 to 11
Challenge level
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Billy's class had a robot called Fred who could draw with chalk held underneath him. What shapes did the pupils make Fred draw?
Hexagon Transformations
problem

Hexagon transformations

Age
7 to 11
Challenge level
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Can you cut a regular hexagon into two pieces to make a parallelogram? Try cutting it into three pieces to make a rhombus!
Rabbit Run
problem

Rabbit run

Age
7 to 11
Challenge level
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Ahmed has some wooden planks to use for three sides of a rabbit run against the shed. What quadrilaterals would he be able to make with the planks of different lengths?

Stellar Angles
problem

Stellar angles

Age
11 to 14
Challenge level
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Weekly Problem 30 - 2013
What is the angle $x$ in the star shape shown?
Outside the Nonagon
problem

Outside the nonagon

Age
11 to 14
Challenge level
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Weekly Problem 44 - 2010
Extend two of the sides of a nonagon to form an angle. How large is this acute angle?
Arrowhead
problem

Arrowhead

Age
14 to 16
Challenge level
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The points P, Q, R and S are the midpoints of the edges of a non-convex quadrilateral.What do you notice about the quadrilateral PQRS and its area?
Linkage
problem

Linkage

Age
11 to 14
Challenge level
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Four rods, two of length a and two of length b, are linked to form a kite. The linkage is moveable so that the angles change. What is the maximum area of the kite?
Cut and Make
problem

Cut and make

Age
7 to 11
Challenge level
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Cut a square of paper into three pieces as shown. Now,can you use the 3 pieces to make a large triangle, a parallelogram and the square again?
Cyclic Quad Jigsaw
problem

Cyclic quad jigsaw

Age
14 to 16
Challenge level
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A picture is made by joining five small quadrilaterals together to make a large quadrilateral. Is it possible to draw a similar picture if all the small quadrilaterals are cyclic?