Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?
What do you notice about the sum of two identical triangular numbers?
Explore the area of families of parallelograms and triangles. Can you find rules to work out the areas?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
Can you decide whether two lines are perpendicular or not? Can you do this without drawing them?
Watch the video to see how to add together an arithmetic sequence of numbers efficiently.
