The radius is the distance from the center to any point. The distance from (2,1) to (0,1) is of course 2. The general formula for a circle with radius r and center (a,b) is

In our case we get
Answer:
-10
Step-by-step explanation:
-12+15=3
(-30)+17=-13
3+(-13)=-10
Answer:The distance between the endpoints (11,−4) and (−12,−4) are 23 units
Step-by-step explanation: