document.write( "Question 1119612: Hi, these are five questions which I need help in
\n" ); document.write( "Write the general equation for the circle that passes through the points:
\n" ); document.write( "(1, 7)
\n" ); document.write( "(8, 6)
\n" ); document.write( "(7, -1)
\n" ); document.write( "Write the general equation for the circle that passes through the points (1, 1), (1, 3), and (9, 2).
\n" ); document.write( "Write the general equation for the circle that passes through the points (- 5, 0), (0, 4), and (2, 4).
\n" ); document.write( "Write the general equation for the circle that passes through the points:
\n" ); document.write( "(-1, 2)
\n" ); document.write( "(4, 2)
\n" ); document.write( "(- 3, 4)
\n" ); document.write( "Write the general equation for the circle that passes through the points:
\n" ); document.write( "(0, 0)
\n" ); document.write( "(6, 0)
\n" ); document.write( "(0, - 8)
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Algebra.Com's Answer #735198 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Principles:\r
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\n" ); document.write( "\n" ); document.write( "The perpendicular bisectors of any chords of a circle intersect in the center of the circle.\r
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\n" ); document.write( "\n" ); document.write( "The slope of a perpendicular bisector is the negative reciprocal of the slope of the original line.\r
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\n" ); document.write( "\n" ); document.write( "The distance from the center to any of the three given points is the radius.\r
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\n" ); document.write( "\n" ); document.write( "Procedure:\r
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\n" ); document.write( "\n" ); document.write( "Select any pair of the given points, and , and use the slope formula to calculate the slope of the line containing those two points.\r
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\n" ); document.write( "\n" ); document.write( "Then calculate the negative reciprocal of this slope, i.e. \r
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\n" ); document.write( "\n" ); document.write( "Use the midpoint formulas to calculate the coordinates of the midpoint, of the chord segment:\r
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\n" ); document.write( "\n" ); document.write( "Derive the slope-intercept form of an equation of the line that has the negative reciprocal slope and passes through the calculated midpoint, thus:\r
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\n" ); document.write( "\n" ); document.write( "Repeat the above process for a different pair of the given points.\r
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\n" ); document.write( "\n" ); document.write( "Take the RHS of each of the derived equations and set them equal to each other. Solve for to obtain the -coordinate of the center of the desired circle. Substitute this value and calculate the -coordinate of the center of the circle. You now have determined the circle center, \r
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\n" ); document.write( "\n" ); document.write( "Use the distance formula with any one of the given points and the center, to calculate the measure of the radius, . Since you will ultimately require only the square of the radius, you need not do the square root step in the distance formula.\r
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\n" ); document.write( "\n" ); document.write( "Finally, construct the Standard Form:\r
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\n" ); document.write( "\n" ); document.write( "And then expand the binomials and collect like terms to create the General Form as required.\r
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\n" ); document.write( "\n" ); document.write( "Where and
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\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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