GCSE Maths Pythagoras and Trigonometry: lesson and practice questions

By the end of this chapter you will be able to

• Use Pythagoras’ theorem to find the hypotenuse or a shorter side, and to decide whether a triangle is right-angled
• Solve Pythagoras problems in context, with coordinates, and in isosceles and equilateral triangles
• Label the sides of a right-angled triangle and use sin, cos and tan to find lengths and angles
• Solve problems with angles of elevation and depression and with bearings
• Know and use the exact values of sin, cos and tan for 0°, 30°, 45°, 60° and 90°

You should already know

• Square numbers and square roots (Chapter 2)
• Rounding to decimal places and significant figures (Chapter 4)
• Rearranging simple equations and formulae (Chapters 8 and 9)
• Angles in a triangle and in an isosceles triangle (Chapter 17)
• Area of a triangle (Chapter 18)

Where this leads

• Bearings, scale drawings and vectors (Chapter 22)
• Trigonometric graphs and functions (Chapter 25, Higher)
• Volume and surface area of cones and pyramids (Chapter 19)