The circumference of a circle = \(\pi d\) or \(2\pi r\). Look at the sector of the circle shown below. To calculate the length of the arc, we need to know what fraction of the circle is shown.

Circle theorems are used in geometric proofs and to calculate angles. Transformations - Edexcel Transformations change the size or position of shapes. Congruent shapes are identical, but may be ...

Our opening quote contended that Venn diagrams are overrated. Even those who agree must admit that they have a curious allure. Take the sets of interesting topics in logic, in geometry and in ...