Question

find the area of a triangle whose perimeter is 180 cm and two of its sides are 80 cm and 18 cm. Also calculate the altitude of the triangle corresponding to the shortest side .

Answer 1

1)
perimeter =180cm

18+80+third side =180
98+ x =180

x=180-98

x=82 cm

2)take all sides like
a=18,b=80,c=82
s= perimeter/2 = 180/2=90

s-a =90-18=72
s-b=90-80=10
s-c=90-82=8

area = root s(s-a)(s-b)(s-c)
= root 90*72*10*8
=root 90*90*8*8
=720 square cm

3) shortest side =base =18 cm

area =720

1/2*base* altitude(h)= 720

h= 720*2/18
h=80cm