Question

An isosceles triangle has perimeter 30cm and each of the equal to equal sides is 12 centimetre find its area of triangle

Answer 1

sum of 3 as sides of a triangle =perimeter x +12+12=30 therefore X=6 . NOW AREA OF TRIANGLE IS √of s(s-a)(s-b)(s-c) where s=a+b+c÷2 there fore answer is S=40 and area = √of (40-12)(40-12)(40-6) =√of 28×28×34=28×33√2=924√2

Answer 2

Answer:

⇒ Area = 9√15 cm²

Step-by-step explanation:

Let the length of the unequal side be x cm.

Then , Perimeter = 30 cm

⇒ x + 12 + 12 = 30

⇒ x + 24 = 30

⇒ x = 6

We have,

⇒ 2s = 30 cm

⇒ s = 15 cm

Therefore,

⇒ Area = √s ( s - a ) ( s - b ) ( s - c )

⇒ Area = √15 ( 15 - 12 ) ( 15 - 12 ) ( 15 - 6 )

⇒ Area = √15 × 3 × 3 × 9

⇒ Area = 9√15 cm²