Question

Segmentul AB este impartit de punctul C in raportul AC supra CB =3 supra 7 si de punctul D in raportul AD supra DB = 9 supra 11.Aflati lungimea segmentului CD, daca AB=120cm.

Answer 1

                                                                      AC/CB=3/7      AD/DB=9/11
A-----------C-------D-------------------------B         (AC+CB)/CB= (3+7)/7       120/CB=10/7   ⇒ CB=84cm  ⇒AC=120-84=36cm            (AD+DB)/DB=(9+11)/11      120/DB=20/11 ⇒DB=66cm ⇒  AD=54cm                      CD=AD-AC=54-36=18cm