Question

Please help thank you sm it would be very helpful and very much appreciated ♥️‼️

2. Write the formula for the circumference of a circle.



a. Calculate the circumference of circle B if the diameter is 8 inches.


b. Calculate the radius of circle B if the circumference is 94.2 square centimeters.

Answer 1

2.circumference= pi×diameter

a)25.136 inches

b)14.99 cm

Explanation:

a) pi × 8

3.142× 8= 25.136

b) diameter = radius × 2

circumference = pi × diameter OR pi × radius×2

because we are trying to find the radius we will use the pi × 2 radius.

94.2= 3.142 × 2 radius

94.2 ÷ 3.142= 2 radius

29.981 = 2 radius

29.981 ÷ 2 = radius

14.99 = radius

Answer 2

Explanation:

2. C =
`2 \pi r`

a. to find radius from diameter in order to calculate the value of the circumference we have to divide the diameter by 2

d/2 = 8/2 = 4

Next, Find the circumference

C =
`2 \pi r`

C =
`2 \cdot 3.142 \cdot 4`

C = 25.13

b. Rearrange formula for circumference to find the value of the radius

Where, C =
`2 \pi r`

Make r the subject of formula

C/
`2 \pi` =
`2 \pi r` /
`2 \pi`

94.2/2 × 3.142 = r

94.2/6.3 = r

r = 14.95 ≈ 15