# NRICH PROBLEM SOLVING ANGLES

During the lesson, as pupils were working their way through one of the most turgid exercises imaginable, I began thinking about how such work might be made more relevant to such classes – that is classes where the evidence shows that a substantial number of children can already manage, with competence, the skill being taught. Triangles in Circles Age 11 to 14 Challenge Level: What happens if you start with a parallelogram? Have you ever noticed how mathematical ideas are often used in patterns that we see all around us? Can you work out how these polygon pictures were drawn, and use that to figure out their angles? Which Solids Can We Make? Polygon Rings Age 11 to 14 Challenge Level:

I was observing a lesson recently in which the teacher was showing her year seven class how to use a protractor. Isometric Drawing Age 11 to 14 Challenge Level: Weekly Problem 10 – If you know how long Meg’s shadow is, can you work out how long the shadow is when she stands on her brother’s shoulders? Weekly Problem 17 – The diagram shows an equilateral triangle touching two straight lines. Pupils could be asked to repeat the exercise with six-point circles drawn with a different radius.

Weekly Problem 41 – The diagram shows a square, with lines drawn from its centre. Can you find the ratio of the area shaded in this regular octagon to the unshaded area? Also, I wanted a means by which practice could be embedded within a more meaningful and mathematically so,ving activity.

DISSERTATION DISTINCTION RÉGIME PARLEMENTAIRE ET RÉGIME PRÉSIDENTIEL

## 301 Matches for angles

Can you find triangles on a 9-point circle? Use your mouse to move the red and green nricu of this disc. Semi-regular Tessellations Age 11 to 16 Challenge Level: Ratty Age 11 to 14 Challenge Level: Weekly Problem 27 – Four congruent isosceles trapezia are placed in a square.

It is my conjecture that there really is, despite Woodhead’s pre-resignation rants and selective use of data to con ministers otherwise, no justification for the misery English schools inflict on their pupils through their indiscriminate use of setting and its predetermination anbles minimal educational attainment for so many. Can you find the area of this square inside a circle?

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Can you work out the size of the angle JFI? Can you find a general rule for explaining when the dot will be this same distance from the horizontal axis? Can you find the value of x in this diagram?

Another line through this point is reflected in both of these lines. Geometry Games Age 5 to 11 Challenge Level: Angles Inside Age 11 to 14 Challenge Level: You may also like Right Time At the time of writing the hour and minute hands of my clock are at right angles. Show that among the interior angles of a convex polygon there cannot be more than three acute angles. Problem Solution Secondary Curriculum Linked.