Question

How do you find the arc length of a semi-circle?

Answer 1

the arc length is calculated by the formula                                                                    $\displaystyle\bf C=\frac{2\pi r}{360} \cdot\alpha$   then   $\displaystyle\bf C=\frac{2\cdot 8 \pi }{360} \cdot180=8\pi=3,14\cdot8=25.12$   or it can be calculated using the circumference of the circle since we have a semicircle the circumference 2πr must be divided by 2  С=2πr:2=πr =8π=25,12