Question

A triangle has sides 39 cm, 80 cm and 89 cm, what is
circumference (in cm) of its incircle?​

Answer 1

Answer:

Given triangle has side lengths of 80 cm ,39 cm,89 cm . ... The given triangle is a right triangle.

Answer 2

Answer: circumference of incircle = 92.4 cm

Step-by-step explanation:

Given : side a of triangle = 39 cm

side b = 80 cm

side c = 89 cm

To find : circumference of incircle

Given sides of the triangle is of right-angled triangle

to find radius of incircle,

incircle is a circle embedded inside of another figure in this case it is a triangle.

r = p + b - h/2

where p is perpendicular b is base and h is height

r = 39+80-89/2

= 39-9/2

= 30/2

=15

hence r of circle = 15cm

Circumference of circle =2 $\pi$ r

Circumference is the perimeter of circle.

= 2 x 3.14 x 15 as $\pi$= 3.14

= 94. 2 cm

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