Question 457978
Center C(2,-3). radius 5
{{{(x-2)^2 + (y+3)^2 = 5^2}}} Standard form of a circle
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Center C(-4,6). passing through P(1, 2)
Find the distance from C to P, that's the radius.
Then it's like the first one.
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Center C(4,-1), tangent to the y-axis
The radius is the distance from C to the y-axis
r = 4
See #1