A circle is centered at the point (-3, 2) and passes through the point (1, 5). The radius of the circle is how many units. The point (-7,? ) lies on this circle.
Accepted Solution
A:
we know that
the equation of a circle is (x-h)²+(y-k)²=r² (h,k) is the center----------> (-3,2)
the radius is the distance point (-3,2) and point (1, 5) d=√(5-2)²+(1+3)²-------> d=√9+16----------> d=5
radius=5 units
equation is (x+3)²+(y-2)²=25
for x=-7 (-7+3)²+(y-2)²=25-------> 16+y²-4y+4=25 y²-4y-5=0
using a graph tool -------> to resolve the second order equation