Find the equation of the circle with centre (-3,2) and radius 8.

Answer: The equation of the circle is (x+3)2+(y−2)2=64(x + 3)^2 + (y - 2)^2 = 64

Step-by-step solution

Step 1: Standard Equation of a Circle

The standard equation of a circle with center (h,k)(h, k) and radius rr is given by this formula. This formula is derived from the distance formula, representing all points (x,y)(x, y) that are a fixed distance rr from the center (h,k)(h, k).

Step 2: Identify Given Values

From the problem statement, we are given that the center of the circle is (−3,2)(-3, 2) and the radius is 88. We identify these values as h=−3h = -3, k=2k = 2, and r=8r = 8.

Step 3: Substitute Values into the Equation

Now, we substitute the identified values of hh, kk, and rr into the standard equation of the circle. This step directly applies the given information to the general formula.

Step 4: Simplify the Equation

We simplify the equation. The term (x−(−3))(x - (-3)) becomes (x+3)(x + 3), and 828^2 simplifies to 6464. This simplified form is the final equation of the circle.

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