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) \n" ); document.write( "

Algebra.Com's Answer #735196 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
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( "-----------------
\n" ); document.write( "You can use a matrix:
\n" ); document.write( "

\r\n" );
document.write( "| x   y   x^2+y^2  1|\r\n" );
document.write( "| 1   7     50     1|\r\n" );
document.write( "| 8   6    100     1| = 0\r\n" );
document.write( "| 7  -1     50     1|\r\n" );
document.write( "\r\n" );
document.write( "

\n" ); document.write( "----------
\n" ); document.write( "I have an Excel sheet that gives the result.
\n" ); document.write( "=============
\n" ); document.write( "Here's the \"hard way:\"
\n" ); document.write( "Label the points A(1,7), B(8,6) and C(7,-1)
\n" ); document.write( "Find the perpendicular bisectors of AB and BC.
\n" ); document.write( "The intersection of those 2 is the center of the circle.
\n" ); document.write( "---
\n" ); document.write( "The distance from the center to any point is the radius.\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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