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TRIGONOMETRY
BY MEGAN ULRICHS
Solving missing sides
STEP 1: DECIDE WHAT TWO SIDES YOU ARE USING - ONE YOU KNOW, THE OTHER YOU ARE TRYING TO SOLVE. (HYPOTENUSE, OPPOSITE, AND ADJACENT)
STEP 2: USE SOHCAHTOA TO DECIDE WHICH OF SIN, COS, AND TAN YOU WILL USE.
STEP 3: SIN= OPPOSITE/HYPOTENUSE
COS= ADJACENT/HYPOTENUSE
TAN= OPPOSITE/ADJACENT
STEP 4: SOLVE USING A CALCULATOR AND PREVIOUS ALGEBRA SKILLS.
ExAMPLE: FIND THE HEIGHT OF THE PLANE
STEP 1: THE TWO SIDES WE ARE USING ARE ADJACENT (H) AND HYPOTENUSE (1000).
STEP 2: SOHCAHTOA TELLS US TO USE COSINE.
STEP 3: PUT OUR VALUES INTO THE COSINE EQUATION: COS 60° + ADJACENT/ HYPOTENUSE = H/1000
STEP 4: SOLVE
START WITH : COS 60° = H/10000
SWAP: H/1000 = COS 60°
CALUATE COS 60°: H/1000 =0.5
MULTIPLY BOTH SIDES BY 1000: H + 0.5 X 1000
H= 500

H= 500 METERS
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