the perimeter of an isoscles triangle is 42 cm and its base is 3/2 times each of equal sides. find the length of each sides. and area

Answer 1

let each of the equal sides be x
then the base is (3/2)x
x+x+3x/2= 42
times 2
4x + 3x = 84
7x = 84
x = 12

sides are 12, 12, and a base of 18

we need the height for area calculation:
make a sketch showing the height, let it be h
I see:
h^2 + 9^2 = 12^2
h^2 = 108
h = √108 = 6√3

area = (1/2)(18)(6√3) = 54√3 cm^2
= appr ......

Answer 2

its ans is
sides are 12,12,18
and h= 71.42

Answer 3

my arithmetic error
144 - 81 = 63 , not 108

so height = √63 = 3√7 = 7.937

area = (1/2)(18)(3√7) = 71.435