ABCD is a cyclic quadrilateral in which AB = 15 cm, BC = 12 cm, and CD = 10 cm. If AC bisects BD, then what is the measure of AD?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 18 cm
AB = 15 cm, BC = 12 cm, CD = 10 cm
ABCD is a cyclic quadrilateral.
Now diagonal AC bisects BD.
Here DO = OB (where O is intersecting point) and
△AOB ~ △COD
⇒ AB/CD = AO/DO
△AOB ~ △COD
⇒ AD/BC = AO/DO
⇒ AB.BC = AD.DC
⇒ AD = (15 × 12)/10 = 18 cm