Question

The perimeter of an isosceles triangle is 30 cm and its equal sides are 12 cm in length. Find the area of ​​this triangle.


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Answer 1

Answer:

Step-by-step explanation:

Let The Third Side Be xcm.

Now Perimeter = 12+12+x

24+x = 30

x = 6

Now Find The Area Using Herons Formula

Semiperimeter = 30/2 = 15

Sq Root(15(15-12)(15-12)(15-6) ) = Sq Root(15*3*3*9) = Sq Root(1215) = 34.85 cm^2

So Area is 34.85cm^2

Answer 2

Let the third side be X CM

Perimeter = 12 + 12 + X = 30

24 + X = 30

X = 30 - 24

X = 6

Area of Herons Formula

Semi Perimeter = 30 / 2 = 15

Area of the traingle = √s (s-a) (s-b) (s-c)

===> √15 ( 15-12) (15-12) (15-6) cm²

===> √15 × 3 × 3 × 9 cm²

===> 9√15 cm²