SOLUTION: A,B,C,D are 4 points on a line such that AB:AC=3:5 and BD:CD=7:2. If CD is 5cm long, find the length of AB?

Algebra ->  Proportions -> SOLUTION: A,B,C,D are 4 points on a line such that AB:AC=3:5 and BD:CD=7:2. If CD is 5cm long, find the length of AB?       Log On


   

Question 66512: A,B,C,D are 4 points on a line such that AB:AC=3:5 and BD:CD=7:2. If CD is
5cm long, find the length of AB?
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
ab:ac=3:5
bd:cd=7:2
if cd is 5 cm then cd=2:5 then ab=3:x
2:5=3:x
15=2x
x=15/2
x=7.5 cm