Question

ABCD is a parallelogram . AE is perpendicular to DC and CF is perpendicular to AD. If AB=18 cm , AE = 8cm and CF= 18 cm. Find AD.

Answer 1

Answer:

In parallelogram ABCD, we have given AB=10cm, AE=8cm, and CF=12cm.

⇒ AB=DC=10cm [Opposite sides of parallelogram are equal]

⇒ Lets find out area of parallelogram with height AE and base DC.

⇒ Area of parallelogram ABCD=b×h

⇒ Area of parallelogram ABCD=DC×AE

⇒ 10×8

∴ Area of parallelogram ABCD=80cm

2

--- ( 1 )

⇒ Now, to find area of parallelogram let CF be the height and AD will be base.

⇒ Area of parallelogram ABCD=CF×AD

⇒ 80=12×AD [From ( 1 )]

⇒ AD=

12

80

∴ AD=6.66cm