document.write( "Question 1205643: Find all points satisfying x+y=0 that are 8 units from (-2,3) \n" ); document.write( "
Algebra.Com's Answer #842577 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "Points that are 8 units from (-2,3) are on the circle \"%28x%2B2%29%5E2%2B%28y-3%29%5E2+=+64\"\r
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\n" ); document.write( "\n" ); document.write( "Solve x+y = 0 for y to get y = -x\r
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\n" ); document.write( "\n" ); document.write( "Plug y = -x into \"%28x%2B2%29%5E2%2B%28y-3%29%5E2+=+64\" to get \"%28x%2B2%29%5E2%2B%28-x-3%29%5E2+=+64\"\r
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\n" ); document.write( "\n" ); document.write( "Do a bit of algebra to get the following
\n" ); document.write( "\"%28x%2B2%29%5E2%2B%28-x-3%29%5E2+=+64\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x%2B4%2Bx%5E2%2B6x%2B9+=+64\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x%2B4%2Bx%5E2%2B6x%2B9-64+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2%2B10x-51+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "Now apply the quadratic formula with: a = 2, b = 10, c = -51\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-10%2B-sqrt%28%2810%29%5E2-4%282%29%28-51%29%29%29%2F%282%282%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-10%2B-sqrt%28100+%2B+408%29%29%2F%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-10%2B-sqrt%28508%29%29%2F%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-10%2B-++22.538855%29%2F%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-10%2B22.538855%29%2F%284%29\" or \"x+=+%28-10-22.538855%29%2F%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2812.538855%29%2F%284%29\" or \"x+=+%28-32.538855%29%2F%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+3.134714\" or \"x+=+-8.134714\"
\n" ); document.write( "Each decimal value is approximate.\r
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\n" ); document.write( "\n" ); document.write( "Each of those x values is plugged into y = -x to find their corresponding paired y value.\r
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\n" ); document.write( "\n" ); document.write( "The two answer points are approximately (3.134714, -3.134714) and (-8.134714, 8.134714) which I've marked as points A and B respectively.\r
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\n" ); document.write( "Point A is located at roughly (3.134714, -3.134714)
\n" ); document.write( "Point B is located at roughly (-8.134714, 8.134714)
\n" ); document.write( "Point C is the center of the circle which is (-2,3)
\n" ); document.write( "AC = 8 and BC = 8 since any point on the circle is 8 units from point C.
\n" ); document.write( "Desmos and GeoGebra are two graphing tools I recommend.
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