Question

A circle is centered at the point (-7, -1) and passes through the point (8, 7).

The radius of the circle is ? units. The point (-15, ?) lies on this circle.

Answer 1

The eq of circle will be
(x+7)^2+(y+1)^2=r^2
Now r is radius of circle.
As the circle passes through (8,7)
It means that this Pt lies on the circumference of the circle. So distance between pt (-7,-1) and (8,7) is r. Substituting the value of r u will get the eq of circle.
Now put x=-15 so u will get the value of y.

Answer 2

for the radius i got 17 units

Answer 3

Yes its correct