GCSE Maths Practice: triangles-and-quadrilaterals

In any triangle, the sum of the three interior angles is always 180°. This rule applies to equilateral, isosceles, and scalene triangles. Knowing this property helps calculate missing angles, solve geometric proofs, and work with polygons. For example, in a triangle with two known angles, the third can be found by subtracting the sum of the known angles from 180°. This principle also underpins angle calculations in quadrilaterals, pentagons, and other polygons by dividing them into triangles. Practicing angle sums in triangles improves diagram interpretation, problem-solving, and reasoning skills. This is essential for GCSE exams and for real-life applications such as construction, architecture, and design. Drawing triangles and labeling angles reinforces understanding of this fundamental property.