Question

In trapezul ABCD, AB||CD, AB=20, CD=10 si AC=15.Daca AC intersectat cu BD=O, atunci lungimea seg. AO este egala cu.....

Answer 1

AOB≈COD(triunghiuri asemenea)⇔[tex] \frac{AO}{OC}= \frac{AB}{DC}= \frac{BO}{OD} [/tex]⇔$\frac{AO}{AO+OC}= \frac{AB}{AB+DC}$⇔$\frac{AO}{15}= \frac{20}{30}$⇔$AO= \frac{15*20}{30}=10 cm$