Angle, symmetry and transformation
Labelling, drawing and measuring angles
Angles are often described using three letters. Angles can be drawn and measured using a protractor.
Finding angles between lines
Complementary angles form a right angle. Supplementary angles form a straight line. Parallel lines in shapes can form corresponding and alternate angles. You can use these properties to find missing angles.
Angles in triangles and quadrilaterals
Angles inside a shape are called interior angles. Interior angles in a triangle add up to 180掳. Interior angles in a quadrilateral add up to 360掳.
Symmetry and 2D shapes
Parts of a shape on either side of a line of symmetry will be exact mirror images of each other. Different two-dimensional shapes have different numbers of lines of symmetry.
Linear scale factor
Similar figures are identical in shape, but generally not in size. A missing length on a reduction/enlargement figure can be calculated by finding its linear scale factor.
