1. Perimeters and SimilarityPerimeters and SimilarityYou will learn to identify and use proportional relationships ofsimilar triangles.1) Scale Factor

2. Perimeters and SimilarityPerimeters and SimilarityThese right triangles are similar!Therefore, the measures of their corresponding sides are ___________.Is there a relationship between the measures of the perimeters of the twotriangles?861012159proportionalWe know that698121015= =Use the ____________ theoremto calculate the length of thehypotenuse.Pythagorean222bac +=23=perimeter of small perimeter of large =9 + 12 + 156 + 8 + 10=3624=32 3. Perimeters and SimilarityPerimeters and Similarityperimeter of ABCperimeter of DEF=DEAB=Theorem9-10If two triangles are similar, thenAC BF EDthe measures of thecorresponding perimeters are proportional to the measuresof the corresponding sides.If ABC ~ DEF, thenEFBC=FDCA 4. Perimeters and SimilarityPerimeters and Similarity27 = 13.5xThe perimeter of RST is 9 units, and RST ~ MNP.Find the value of each variable. MN4.5PRST 36zYxperimeter of MNPperimeter of RSTRSMN=13.59x3=Theorem 9-10The perimeter of MNP is 3 + 6 + 4.5Cross Productsx = 2RSMN=STNPRSMN=TRPM23=y623=z4.53y = 12 3z = 9y = 4 z = 3 5. Perimeters and SimilarityPerimeters and SimilarityDEAB=EFBCFDCA=Each ratio is equivalent to21If ABC ~ DEF, thenThe ratio found by comparing the measures of corresponding sides ofsimilar triangles is called the constant of proportionality or the ___________.scale factorAB C753DE F14106or63=147=105The scale factor of ABC to DEF is21The scale factor of DEF to ABC is12 6. Perimeters and SimilarityPerimeters and Similarity 7. Perimeters and SimilarityPerimeters and Similarity