Algebra II : Circle Functions

Study concepts, example questions & explanations for Algebra II

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Example Questions

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Example Question #11 : Circle Functions

Determine the center and radius, respectively, given the equation: 

Possible Answers:

Correct answer:


In order to solve for the radius, we will need to complete the square twice.  

Group the x and y-variables in parentheses.  Starting from the original equation:

Add two on both sides. 

Divide by the second term coefficient of each binomial by 2, and add the squared quantity on both sides of the equation.

The equation becomes:

Factorize both polynomials in parentheses and simplify the right side.

The center is: 

The radius is:  

The answer is:  

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