Trigonometry

Unit 4:Mathematics Aims Jog your memory on Pythagoras therom and Trigonometry Objectives Identify lengths and angles of right angle triangles using formulas.

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Right angled triangle hypotenuse opposite adjacent

hypotenuse opposite adjacent There are three ratios that you need to learn: hypotenuse opposite adjacent

Finding a length hypotenuse opposite adjacent 10cm You need to label all the lengths of the triangle. hypotenuse 10cm The adjacent is not needed in this question; the question is only using opposite and hypotenuse. opposite adjacent

Finding a length hypotenuse opposite You need to label all the lengths of the triangle. The adjacent is not needed in this question; the question is only using opposite and hypotenuse. hypotenuse 10cm opposite

Finding a length hypotenuse 10cm opposite

Finding a length hypotenuse opposite 10cm OR rearrange the equation (*) by multiplying both sides by x.

These two triangles are very different. The variable x will be on the denominator This is an example of where we have to solve an equation with the variable on the denominator, so multiply both sides by x. still need to get x on its own, so divide both sides by sin30

2. Pick the correct formula 1.Label the triangle 3.Substitute in the correct values opposite 15cm adjacent 4. Rearrange to find x

15cm opposite adjacent

Datryswch yr trionglau canlynol iawn gyda'r mesuriadau a roddir Solve the following right triangles with the dimensions given 5 c 22 A B C A a c 13 B C 52 º 9 20 18 A B C c 12 8 º A B C