Answer:
1/2pi
Step-by-step explanation:
Since the formula for circumference is 2*pi*r and we know the R=1 so the of the whole circle is 2pi. This is a quarter of a circle so the answer is 1/2pi
x=55
x/5=11
11x5=55
All you gotta do is subtract - b + c from both sides then simplify.