Answers to Homework 2) 1:14) 5:16) 6 to 5 8) 11 to 1210) 11/1712) 6:5:12 14) 6:11:1716) 5:318) 20:17 20) 1:522) 2d/5c24) 40,50 26) 45,60,7528) 67.5,67.5,45 30) 32,44,56
7-2 Properties of Proportions
Proportion = 2 equal ratios same as cross multiply swap reciprocal add bottom # then
Example First Outer Inner Last
Try On Own (both answers are fractions) 1) 2) Answers: 1) x = 10/3 2) x = -20/3
Example A B C D E What else do you know? Given ED = 2, DC = 6, and AB = 3 Find BC, AC, and EC EC = = 8 2BC = 18, BC = 9 AC = = 12
Example A B C D E Given AB = 12, BC = 4, and EC = 20 Find ED, DC, and AC AC = = 16 Cross Multiply, ED = 15 DC = 20 – 15 = 5 x 20 – x
TOO A B C D E 1)Given AB = 8, AC = 10, and ED = 12 Find BC, DC, and EC. 2)Given AC = 30, ED = 28, and EC = 42 Find AB, BC, and DC. 1) BC = 2 DC = 3 EC = 15 2) AB = 20 BC = 10 DC = 14
Homework Pg 247 #1-8 all 9-27 odd all