Question

Qolf the perimeter of Isosceles is 30cm. If two of its equal sides are 8cm each. Find the third​

Answer 1

Answer:

Area of triangle =

S(S−a)(S−b)(S−c)

Here S is the semi- perimeter, and a,b,c are sides of the triangle

The given triangle is isosceles.

In isosceles triangle, two sides are equal

so, a=b=12 cm

and perimeter =30 cm

semi perimeter =

2

perimeter

S=

2

30

S=15 cm

We find C,

perimeter =30 cm

a+b+c=30 cm

⇒ 12+12+c=30 cm

⇒ 24+C=30 cm

⇒ C=30 cm −24 cm

⇒ C=6 cm.

Area of triangle =

15(15−12)(15−12)(15−6)

=

15.3.3.9

=

15.9.9

=

9

2

.15

=9

15

cm

2

∴ Area of triangle = 9

15

cm

2

so, the answer is C−− 9

15

cm

2