Hello, coobe!

Let be a solution to the equation.Determine the set of solutions for: .

Hint: Try to find an equation in form of a general circle.

is the distance of point from point

is the distance of point from point

We are told that: .

. . Hence: .

Square and expand: .

Simplify: .

Complete the square: .

Therefore: .

. . The solution is a circle with center and radius 4.

Note: It is known as theCircle of Apollonius.

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