Question

What is the exact Length of AB?

Answer 1

the answer is pi.
to find this, you find the circumference of a circle with a 4m radius, which is 2pi(4) or 8pi. then you need find the fraction of the circle that this angle is. a circle is 360degrees, so 45/360 is 1/8.

1/8 x 8pi = pi -> pi m

Answer 2

pi

Explanation:

First find the circumference of a circle with radius 4

C = 2 * pi *r

C = 2*pi*4

C = 8pi

A circle has 360 degrees

Find the fraction of a circle that 45 degrees is

45/360 = 1/8

Multiply the fraction by the circumference

1/8 *8pi = pi