Question

∆ABC is an equilateral triangle with side 21 cm. Find the perimeter of the given figure​

Answer 1

Answer:

Given:∆ABC is an equilateral triangle with side 21 cm.

Therefore,Radius of the Semicircle=21/2.

The perimeter of the given figure=Circumference of the 3 semicircles+Perimeter of the Equilateral Triangle.

=[3(1/2X2πr)+3XSide.]cm.

=[3Xπr+3XSide.]cm.

=[3X22/7X21/7+3X21]cm.

=[28.2857143+63]cm.

=91.2857143cm.

Answer 2

Answer:

To, start of with.

let us revise one important formula to solve this question.

the perimeter of the circle is

$2\pi \: r$

so perimeter of half the circle would be

$\pi \: r$

now let's solve the question.

we see that there are 3 semi circle in the figure.

which makes it 1 circle (whole) and one semi circle

let's find the perimeter of one whole circle

if we place the no. in the formula we get

( refer to the first formula)

$2 \times \frac{22}{7} \times 21$

cancel out 7 from 21 .

$2 \times 22 \times 3 = 132$

now perimeter of half semi circle

+ refer to second formula!

$\frac{22}{7} \times 21 = 66 \\ cancel \: 7 \: and \: 21$

now add the numbers

66 cm+ 132 cm = 198 cm

I hope that this helps you

mark the answeras brainliest!!!

perimeter refer s to the outline keep in mind

have a great day ahead