document.write( "Question 1156565: The problem is stated thus: A circle is tangent to the y-axis at y=3 and has one x-intercept at x=1.
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\n" ); document.write( "b. deduce the equation of the circle
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Algebra.Com's Answer #779291 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
The first thing I would do is draw a diagram and label some points.\r
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\n" ); document.write( "\n" ); document.write( "Since the distance from the center of the circle \"C\" to \"P\" is \"r\"\r
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\n" ); document.write( "\n" ); document.write( " \"%28r+-1%29%5E2%2B+%283+-0%29%5E2+=+r%5E2\" \r
\n" ); document.write( "\n" ); document.write( "Solve for \"r\".\r
\n" ); document.write( "\n" ); document.write( "\"r%5E2-2r%2B1+%2B+9+=+r%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"r%5E2-r%5E2+-+2r%2B1+%2B+9+=+0\"\r
\n" ); document.write( "\n" ); document.write( " \"-2r%2B10+=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"+10+=2r\"\r
\n" ); document.write( "\n" ); document.write( "\"r=5\"\r
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\n" ); document.write( "\n" ); document.write( "yor equation is:\r
\n" ); document.write( "\n" ); document.write( " \"%28x+-+h%29%5E2+%2B+%28y-k%29%5E2+=+5%5E2\".........use given point (\"1\",\"0\") to find \"h\" and \"k\"\r
\n" ); document.write( "\n" ); document.write( "\"%281+-+h%29%5E2+%2B+%280-k%29%5E2+=+25\"\r
\n" ); document.write( "\n" ); document.write( "\"1+-+2h%2Bh%5E2+%2B+k%5E2+=+25\"\r
\n" ); document.write( "\n" ); document.write( "\"+-+2h%2Bh%5E2+%2B+k%5E2+=+24\"......eq.1\r
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\n" ); document.write( "\n" ); document.write( " \"%28x+-+h%29%5E2+%2B+%28y-k%29%5E2+=+5%5E2\".........use given point (\"0\",\"3\") \r
\n" ); document.write( "\n" ); document.write( "\"%280+-+h%29%5E2+%2B+%283-k%29%5E2+=+25\"\r
\n" ); document.write( "\n" ); document.write( "\"h%5E2+%2B+k%5E2-6k+%2B9=+25\"\r
\n" ); document.write( "\n" ); document.write( "\"h%5E2+%2B+k%5E2-6k+=+16\"..............eq.2\r
\n" ); document.write( "\n" ); document.write( "solve the system:\r
\n" ); document.write( "\n" ); document.write( "\"+-+2h%2Bh%5E2+%2B+k%5E2+=+24\"......eq.1
\n" ); document.write( "\"h%5E2+%2B+k%5E2-6k+=+16\"..............eq.2
\n" ); document.write( "---------------------------------------------------------subtract\r
\n" ); document.write( "\n" ); document.write( "\"+-+2h%2Bh%5E2+%2B+k%5E2-%28h%5E2+%2B+k%5E2-6k%29+=+24-16\"\r
\n" ); document.write( "\n" ); document.write( "\"+-+2h%2Bh%5E2+%2B+k%5E2-h%5E2+-+k%5E2%2B6k+=+8\"\r
\n" ); document.write( "\n" ); document.write( "\"+-+2h+%2B6k+=+8\"\r
\n" ); document.write( "\n" ); document.write( "\"+-+h+%2B3k+=+4\"......solve for \"h\"\r
\n" ); document.write( "\n" ); document.write( "\"+-+4%2B3k+=+h\".........eq.1a\r
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\n" ); document.write( "\n" ); document.write( "go to\r
\n" ); document.write( "\n" ); document.write( "\"h%5E2+%2B+k%5E2-6k+=+16\"..............eq.2, substitute \"h\"\r
\n" ); document.write( "\n" ); document.write( "\"%28-+4%2B3k%29%5E2+%2B+k%5E2-6k+=+16\"......solve for \"k\"\r
\n" ); document.write( "\n" ); document.write( "\"10+k%5E2+-+30+k+%2B+16+=+16\"\r
\n" ); document.write( "\n" ); document.write( "\"10+k%5E2+-+30k++=+16-16\"\r
\n" ); document.write( "\n" ); document.write( "\"10+k%5E2+-+30k++=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"+k%5E2+-+3k++=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"k%28+k+-+3%29++=+0\"\r
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\n" ); document.write( "\n" ); document.write( "=>\"k+=+0\" or\"+k+=+3\"\r
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\n" ); document.write( "\n" ); document.write( "go to \"+-+4%2B3k+=+h\".........eq.1a, substitute \"k\"\r
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\n" ); document.write( "\n" ); document.write( "\"+-+4%2B3%2A0+=+h\"=>\"h=-4\"\r
\n" ); document.write( "\n" ); document.write( "\"+-+4%2B3%2A3+=+h\"=>\"h=5\"\r
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\n" ); document.write( "\n" ); document.write( "solutions for coordinates of the center
\n" ); document.write( "\"h+=+-4\", \"k+=+0\"=> disregard, because point (\"0\",\"3\") is a point where circle touches y-axis\r
\n" ); document.write( "\n" ); document.write( "your coordinates of the center:\r
\n" ); document.write( "\n" ); document.write( "\"h+=+5\", \"k+=+3\"\r
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\n" ); document.write( "\n" ); document.write( "and your equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x+-+5%29%5E2+%2B+%28y-3%29%5E2+=+25\"\r
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