Question

The perimeter of triangular field is 20 dm . If two sides are 78 dm and 50 dm find the length of perpendicular on the side of length 50 dm from opposite vertex

Answer 1

Your Question is wrong , corrcted question given below.

Q)The perimeter of triangular field is 240 dm . If two sides are 78 dm and 50 dm find the length of perpendicular on the side of length 50 dm from opposite vertex

Solution :-

Perimeter of the triangle = 240 dm

Two sides (given) = 78 dm and 50 dm

Third side of the triangle = 240 - (78 + 50)

= 240 dm - 128 dm

= 112 dm

s = (a + b + c)/2

= (78 + 50 + 112)/2

= 240/2

s = 120 dm

Area of the triangle = √s(s - a)(s - b)(s - c)

⇒ √120 (120 - 50)(120 - 78)(120 - 112)

⇒ √120*70*42*8

⇒ √2822400

Area of the triangle = 1680 sq dm

Now,

Area of the triangle = 1/2*base*height

Height = 2*area/base

⇒ (2*1680)/50

⇒ 336/5

height = 67.2 dm