Question

the sides of a triangle are 8cm,15cm and 17 cm. find its area

Answer 1

s=(8+15+17)/2=20.
area of triangle =square root of (s(s-8)(s-15)(s-17))
=square root of(20(20-8)(20-15)(20-17)
=square root of(20*12*5*3)
= square root of(4*5*4*3*5*3)
=4*5*3=60cm^2.

Answer 2

Answer:

Area of the triangle $A = 60 cm ^{2}$

Explanation:

Let the three sides of a triangle are ,

a = 8cm,

b =15 cm,

c = 17 cm

/* we know that,

$s =\frac{a+b+c}{2}$ */

Now,

substitute a,b and c values, we get

$s =\frac{8+15+17}{2}$

$\implies s =\frac{40}{2}$

$\implies s = 20$

s-a = 20-8 = 12

s-b = 20-15 = 5

s-c = 20-17 = 3

/* we know that,

Area of the triangle (A)

$\boxed {A = \sqrt{s(s-a)(s-b)(s-c)}}$ */

$\implies A = \sqrt{20\times 12\times 5 \times 3}$

$\implies A = \sqrt{3600}$

$\implies A = \sqrt{60^{2}}$

$\implies A = 60 cm ^{2}$

Therefore,

Area of the triangle $A = 60 cm ^{2}$

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