Find the area of a triangle whose sides are 9 cm, 12 cm and 15 cm. – InterviewSolution

InterviewSolution

1.

Find the area of a triangle whose sides are 9 cm, 12 cm and 15 cm.

Answer»

Let a, b and c are the sides of triangle and s is the semi-perimeter, then its area is given by:

A = \(\sqrt{s(s-a)(s-b)(s-c)}\) where s = \(\frac{a+b+c}{2}\) [Heron’s Formula]

a = 9, b = 12, c = 15

s = \(\frac{a+b+c}{2}\) = \(\frac{9+12+15}{2}\) = 18

A = \(\sqrt{18(18-9)(18-12)(18-15)}\)

A = \(\sqrt{18 \times9 \times6 \times3}\) = 54 cm²

Discussion

No Comment Found

Related InterviewSolutions

The area of an isosceles triangle having base 2 cm and the length of one of the equal sides 4 cm, is A. √15 cm2 B. √15/2 cm2 C. 2√15 cm2 D. 4√15 cm2
Find the area of a triangle whose sides are 3 cm, 4 cm, and 5 cm respectively.
If the area of an equilateral triangle is 16√3 cm2, then the perimeter of the triangle is A. 48 cm B. 24 cm C. 12 cm D. 36 cm
The length of each side of an equilateral triangle having an area of 9√3 cm2 isA. 8 cmB. 36 cmC. 4 cmD. 6 cm
The sides of a triangle are 56 cm, 60 cm and 52 cm long. Then the area of the triangle is(A) 1322 cm2(B) 1311 cm2(C) 1344 cm2(D) 1392 cm2
The perimeter of a triangle is 300 m. If its sides are in the ratio 3 : 5 : 7. Find the area of the triangle.
A triangle has sides 35 cm, 54 cm and 61 cm long. Find its area. Also, find the smallest of its altitudes.
The perimeter of a triangular field is 420 m and its sides are in the ratio 6:7:8. Find the area of the triangular field.
Write True or False and justify your answer:The area of a triangle with base 4 cm and height 6 cm is 24 cm2.
The lengths of the sides of a triangle are in the ratio 3 : 4 : 5 and its perimeter is 144 cm. Find the area of the triangle and the height corresponding to the longest side