Question

an isosceles triangle has perimeter 30cm and each of the equal sides is12cm find the area of the triangle

Answer 1

$<b>$ hey mate

here's your answer,

$\huge{ Note :}$

two sides of an isosceles triangle is equal ...

perimeter of triangle = 30cm

measure of the equal sides = 12cm each

let take the third side as x

perimeter of triangle = sum of all sides

》 30cm= 12cm + 12cm + x
》 30cm - 24cm = x
》 6cm = x

$\therefore$ the third side is equals to 6cm .....

area of an isosceles triangle = $\huge\frac{Base × Height }{2}$ = $\huge\frac{6cm × 12cm}{2}$ = 26${cm}^{2}$

hope it helps you mate ✔✔

be brainly ✔✔

Answer 2

☆ Solution ☆

Given :-

An isosceles triangle has perimeter 30cm and each of the equal sides is 12 cm.

To Find :-

The area of the triangle.

Step-by-Step-Explaination :-

Let the third side be x

So,

12 + 12 + x = 30

24 + x = 30

x = 30 - 24

x = 6

Hence,

The length of the third side is 6 cm.

Now,

The semi perimeter of the isosceles triangle (s) = 30/2 cm = 15 cm

By using Heron's Formula,

As we know that :-

Area of triangle = √ s ( s - a ) ( s - b ) ( s- c )

Putting the respective value,

√ 15 ( 15 - 12 ) ( 15 - 12 ) ( 15 - 6 ) cm²

√ 15 × 3 × 3 × 9 cm²

9 √ 15 cm²

Hence Solved !