Question

find the area of an isoceles triangle whose base is 18 cm and one of its equal sides is 15 cm ? full explanation pls​

Answer 1

Step-by-step explanation:

Given : An isosceles triangle whose base is 18 cm and one of its equal sides is 15cm

To Find: Area

Solution:

Since we are given that base is 18 cm and one of its equal sides is 15cm

So, sides of triangle: a=15 ,b=15 , c=18

We will use heron's formula:

Area = \sqrt{s(s-a)(s-b)(s-c)}Area=

s(s−a)(s−b)(s−c)

Where s= \frac{a+b+c}{2}s=

2

a+b+c

Now a=15

b=15

c=18

So, substitute the values in formula

s= \frac{15+15+18}{2}s=

2

15+15+18

s= 24s=24

Area = \sqrt{24(24-15)(24-15)(24-18)}Area=

24(24−15)(24−15)(24−18)

Area =108 cm^2Area=108cm

2

Hence the area of given triangle is 108 square cm