SOHCAHTOASOHCAHTOA recalls right-triangle ratios: Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent. Use a chosen acute angle, between 0° and 90°.
You’ll leave with these skills
01Find the sine, cosine, and tangent of an angle in a right triangleLabel the opposite and adjacent sides from the angle the question names, then divide the two sides that sine, cosine, or tangent uses.
02Find an angle when its sine equals another angle’s cosineSet the two angles to add up to 90 degrees and solve for the missing one.
03Find a trig ratio from a similar triangleWrite the ratio from the matching angle in whichever triangle shows the side lengths.
04Find one angle’s tangent from the other angle’s sineUse the sine’s top and bottom numbers as two side lengths, find the third side, and relabel opposite and adjacent from the other angle.
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207 lessons that teach every skill the SAT tests
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40Reading
24Grammar
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