Question

What is the arc length of a semicircle if the diameter is 10?

Please help me with this! I have tried and tried and just couldn't get the answer! PLEASE HELP ME!!! DX

Answer 1

`15.71`

Explanation:

The arc length of a circle has it's own formula:

`m^@/(360^@)pid`

`m^@ = "angle measure of arc"`
`d = "diameter"`

Since this is a `"semicircle"`, the angle measure of the arc is going to be `180^@`. And they said that the diameter is `10`, so we can update the formula:

`(m)/(360)pid`

`180/360pi(10)`

`0.5pi10`

`5pi`

Use your calculator to find the value of `5pi` or use the number `3.1415927` for `pi` if you have to do it manually.

`5pi = 15.71`

So the arc measure of the semi circle is `15.71`