Well, I dont know these simple questions, hope someone can answer them
1.
Given 2 points A(2,-5) and B(-4,3)
Find the equation of the circle with diameter AB.
Answer: x^2+2x+y^2+2y-23=0
2.
A circle has centre c(-1,3) and radius 5 units.
The line 3x-y+1=0 meets the circle at 2 points. Find...