Question

In fig. 12.5, ✂ abc has sides ab = 7.5 cm, ac = 6.5 cm and bc = 7 cm. On base bc a parallelogram dbce of same area as that of ✂ abc is constructed. Find the height df of the parallelogram

Answer 1

Answer:

Step-by-step explanation:

by using herons formula , √s(s-a)(s-b)(s-c)=ar of Δle

 s=7.5+6.5+7/2=21/2cm

a=7.5cm b=6.5cm c=7cm

⇒ar of Δle=√21/2(10.5-7.5)(10.5-6.5)(10.5-7)

                 =√21/2(3)(4)(7/2)

                 =21/2×2

                 =21cm²

given, ar of Δle=ar of ║gm

       ⇒ 21=bh

       ⇒ 21=7×h

h of ║gm =3cm

⇒1/2 bh=bh

base is same

⇒h=2h

h of Δle= 2×h of║gm

            =2×3

           =6cm