Question

the base of an isosceles triangle measures 80 cm and its area is 360 CM square find the perimeter of the triangle

Answer 1

base=80 cm

area=(b*h)/2

360=(80*h)/2

360=40*h

h=9 cm

perimeter =2a +b(a is the  one of the two equal sides of triangle and b is base)

a can be calculated using pythagoras theorem as isosceles triangle when divided into half along base forms two right angled triangle

half of base=40 cm

side=?

height=9 cm

(side)²=(height)²+(base)²=(9)²+(40)²=81+1600=1681

(side)²=1681=(41)²

side=41 cm

perimeter=2(side)+base=2(41)+80=82+80=162