Answer:
45
Step-by-step explanation:
-45 + 30 gives you -15. When subtractinf a negative number, it actually turning into addition/positive. This changes it into -15 + 60, which is 45.
It has to be C- addition and subtraction signs.
The formula is L = 2 pi r * (angle measure / 360). We have everything we need to solve this, the angle is 90 and the radius is 12: L = 2 pi (12) (90/360). Do the work inside the parenthesis first to get : L = 2 pi (12)(.25). Solving for L: L = 6pi
