The adjacent sides of a parallelogram ABCD measure 34 cm and 20 cm, and the diagonal AC measures 42 cm. Find the area of the parallelogram.
Given:
AB = 34 cm
BC = 20 cm
AC = 42 cm
In ∆ABC (scalene),
Area of ∆ABC = √(s(s-AB)(s-BC)(s-AC))
Where,
⇒ s = 48 cm
Now,
Area of a scalene triangle = √(48cm × (48-42)cm × (48-20)cm × (48-34)cm)
= √(48 cm × 6 cm × 28 cm × 14 cm)
= √112896 cm2
= 336 cm2
Now,
Area of parallelogram ABCD = 2 × Area of ∆ABC
= 2 × 336 cm2
= 672 cm2