SOLUTION: Find the length of a circle if the radius extends form (-1,2) to (0,-1). Use the radius to find the area fo the circle (leave your answer in terms of Pi)

Algebra ->  Linear-equations -> SOLUTION: Find the length of a circle if the radius extends form (-1,2) to (0,-1). Use the radius to find the area fo the circle (leave your answer in terms of Pi)       Log On


   

Question 421312: Find the length of a circle if the radius extends form (-1,2) to (0,-1). Use the radius to find the area fo the circle (leave your answer in terms of Pi)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

the radius extends form (-1,2) to (0,-1); so, find the distance between these points
Solved by pluggable solver: Distance Formula to determine length on coordinate plane
The distance (d) between two points is given by the following formula:

d=sqrt%28%28x2-x1%29%5E2+%2B+%28y2-y1%29%5E2%29

Thus in our case, the required distance is
d=sqrt%28%280--1%29%5E2+%2B+%28-1-2%29%5E2%29=+3.16227766016838+


For more on this concept, refer to Distance formula.




the distance=radius; so, the radius r=3.16
find the area of the circle:
A=r%5E2%28pi%29
A=%283.16%29%5E2%28pi%29
A=%289.9856%29%28pi%29...round it
A=10%28pi%29