Question

7. Find the area of a triangle whose sides are 17 cm, 10 cm and 9 cm.​

Answer 1

Three sides of triangles: 17cm,10cm,9cm

s= a+b+c/2

= 17cm=10cm+9cm/2

= 18cm

area of triangle from heron's formula

s√(s-a)(s-b)(s-c)

= √18(18-17cm)(18-10cm)(18-9cm)

=  36cm^2

Answer 2

Step-by-step explanation:

Given -:

• Sides of a triangle = 17cm, 10cm and 9cm

To Find -:

• Area of the triangle

Explanation -:

Let a = 17cm, b = 10cm and c = 9cm

Then,

$\small \boxed{\bf{s = \frac {a + b + c}{2}}}$

$\small\rm {s = \: \frac{17 + 10 + 9}{2} = \frac{36}{2} = 18}$

(s - a) = (18 - 17) = 1

(s - b) = (18 - 10) = 8

(s - c) = (18 - 9) = 9

$\small \boxed{\bf {Area \: of \: a \: triangle = \sqrt{s(s - a)(s - b)(s - c)} }}$

$= \small\rm{ \sqrt{18 \times 1 \times 8 \times 9} }$

$= \small\rm { \sqrt{2 \times 3 \times 3 \times 2 \times 2 \times 2 \times 3 \times 3} }$

$= \small\rm{2 \times 2 \times 3 \times 3}$

$= \small\rm{36 {cm}^{2} }$

$\small \boxed{\rm{ Area \: of \: a \: triangle = 36 {cm}^{2} }}$