Question

An isosceles triangle has perimeter 32 cm and each of the equal sides is 10 cm. Find

the area of the triangle.​

Answer 1

Answer:

Perimeter of isosceles triangle=30cm

Length of equal sides=12cm

Let third side of triangle=xcm

According to problem,

x+12+12=30

x+24=30

x=30−24

x=6

∴ Third side of triangle=6cm

Using Heron's formula

Area of triangle=  

s(s−a)(s−b)(s−c)

​  

 sq. units

where s=  

2

a+b+c

​  

 

s=  

2

30

​  

=15

Area of triangle=  

15(15−12)(15−12)(15−6)

​  

cm  

2

 

=  

15×3×3×9

​  

cm  

2

 

=3×3×  

15

​  

cm  

2

 

=9  

15

​  

cm  

2

 

∴ Area of triangle=9  

15

​  

cm  

2

.