Find the area of a circle whose diameter has the endpoints (-1,3) (3,1)

Question

Hi, I need help solving the question in the title. Thanks 

Answer 1

Alex,

 

One formula for the area of a circle is:

 

πd where d is the diameter of the circle.  Use the distance formula to find the diameter and then multiply by pi. 

 

Oops, that's the circumference.

 

Use pi*r²  where r is half the diameter