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Use Proportions to Solve Geometric Problems 6.2 Proportion Properties • The Reciprocal Property: – If two ratios are equal, then their reciprocal is also equal. – Basically, you can flip ratios to make new equivalent ratios. Examples If 6 x , 7 14 then 14 7 6 x Proportion Properties • If you have 2 ratios equal to each other, then the numerators can be turned into a new ratio and the denominators into another new ratio. Examples Proportion Properties cont. • You can add the denominator of each ratio to the numerator to get a new ratio. Examples True or False? true true false true True or False? false true true true True or False? false true true BA = 12, BD = x – 3 = 12 – 3 = 9 What do I know? XW = 1, XY = 3, YZ = 2, and WV is unknown so WV = x 1 3 x 2 1(2) = 3x 2 = 3x 2 x 3 SR = 3, RQ = 4, ST = 6, and TU = x 3 6 4 x 3x 6(4) 3x 24 x8 BC = x, AB = 12, CD = 24, and DE = 18 x 24 12 18 18x 12(24) 18 x 288 x 16 HI = 21, GH = 14, JK = x, and KD = 12 21 x 14x 21(12) 14 x 252 x 18 14 12 JD JK KD 18 12 30 Worksheet