…there are three trig ratios The Trigonometric ratios: …there are three trig ratios opposite hypotenuse Sine ratio = hypotenuse opposite adjacent hypotenuse Cosine ratio = adjacent opposite adjacent Tangent ratio =

Find angle ABC. x A B C 8cm 12cm opposite Label the sides. sin x0 = hypotenuse 8 opp hyp sin x0 = 12 sin x0 sin-1 = 0.6666 x x = 420 Choose a ratio. opp hyp Sin = adj hyp Cos = opp adj Tan =

Find angle ABC. Label the sides. adjacent cos x0 = hypotenuse 10cm A B 18 cos x0 = cos-1 0.5555 hyp x = 560 Choose a ratio. opp hyp Sin = adj hyp Cos = opp adj Tan =

Find the length of side BC. Label the sides. A B C 640 15cm adjacent cos 640 = hypotenuse hyp x adj x cos 640 = 15 x x cos 640 = x 15 6.6cm = x Choose a ratio. opp hyp Sin = adj hyp Cos = opp adj Tan =

Find the length of side AB. Label the sides. opp x opposite A B C 11cm 580 tan 580 = adjacent adj x tan 580 = 11 x x tan 580 = x 11 17.6cm = x Choose a ratio. opp hyp Sin = adj hyp Cos = opp adj Tan =

Find the length of side AB. C 7cm 270 Label the sides. opposite sin 270 = hypotenuse opp x hyp 7 sin 270 = x 7 sin 270 = = x x = 15.4cm Choose a ratio. opp hyp Sin = adj hyp Cos = opp adj Tan =

Find the length of side BC. A C B 5.8cm 390 Label the sides. opposite tan 390 = adjacent 5.8 tan 390 = adj x x 5.8 tan 390 = = x x = 7.2cm Choose a ratio. opp opp hyp Sin = adj hyp Cos = opp adj Tan =