Question

In a trapezium ABCD, seg AD seg BC and E is the point of
intersection of diagonals AC and BD Find the value of x from
the information given in the figure​

Answer 1

Given:  

side AB || side DC

AB = 20,

DC = 6,

OB = 15

In △COD and △AOB

∠COD = ∠AOB         (Vertically opposite angles)

∠CDO= ∠ABO         (Alternate angles, CD ||BA and BD is a transversal line)

By AA test of similarity

△COD ∼ △AOB

∴CDAB=ODOB                      (Corresponding sides are proportional)⇒620=OD15⇒OD=4.5