Question

Find the area of a triangle whose perimeter is 180 cm and two of its sides are 80 cm

and 82 cm respectively.​

Answer 1

Answer:

Side a = 80 cm

Side b = 82 cm

Perimeter of triangle = Side a + Side b + Side c

180 = 80 + 82 + Side c

180 = 162 + Side c

180 - 162 = Side c

18 cm = Side c

Side a = 80 cm

Side b = 82 cm

Side c = 18 cm

Semiperimeter of triangle = a + b + c / 2

= 80 + 82 + 18 / 2

= 180 / 2

= 90 cm

By heron's formula,

Area of triangle = √s(s-a)(s-b)(s-c)

= √90(90-80)(90-82)(90-18)

= √90x10x8x72

= √90x8x10x72

= √720x720

= 720 cm^2