Find the length of arc shown in red.

10.99 ≈ 11cm

Step-by-step explanation:

To find the length of the arc, first we need to find the circumference of the circle, which we find with the following formula :

where   is the radius which is indicated in the image: .

so the circumference  is:

This is the measure of the entire perimeter of the circle, it is the measure of the 360 ° arc.

Because we only want 45 ° of those 360 °, we divide the value of the circumference by 360 and multiply po 45:

which can be rounded to 11cm

The length of the arc is 11cm