Answer:
1. Centre = (1,-3); r = 2;
2. Centre = (2,-1); r = 4
Step-by-step explanation:
1. (x - 1)² + (y + 3)² = 4
The centre-radius equation for a circle is
(x - h)² + (y - k)² = r²
The centre of the circle is at (h, k) and the radius is r.
By comparing terms in the two equations we see that
h = 1, k = -3, r = 2
Centre = (1,-3); r = 2
2. (x - 2)² + (y + 1)² = 16
Here,
h = 2, k = -1, r = 4
Centre = (2,-1); r = 4
The figure below shows the first circle in red and the second in green.
