Find the equation of the circle with centre (-3,2) and radius 6.

Answer: The equation of the circle is (x+3)2+(y−2)2=36(x+3)^2 + (y-2)^2 = 36.

Step-by-step solution

Step 1: Recall the standard equation of a circle

The standard equation of a circle is given by (x−h)2+(y−k)2=r2(x-h)^2 + (y-k)^2 = r^2, where (h,k)(h,k) represents the coordinates of the center of the circle and rr represents its radius.

Step 2: Identify the given values

From the problem statement, we are given that the center of the circle is (−3,2)(-3{,}2) and the radius is 66. Therefore, we can identify h=−3h = -3, k=2k = 2, and r=6r = 6.

Step 3: Substitute the values into the equation

Now, substitute the identified values of hh, kk, and rr into the standard equation of the circle. This gives us (x−(−3))2+(y−2)2=62(x - (-3))^2 + (y - 2)^2 = 6^2.

Step 4: Simplify the equation

Simplify the expression. Subtracting a negative number is equivalent to adding a positive number, so (x−(−3))(x - (-3)) becomes (x+3)(x+3). Also, calculate 626^2, which is 3636.

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