document.write( "Question 885998: P(x,2x)\r
\n" ); document.write( "\n" ); document.write( "The ordinate of a point P is twice the abscissa. This point is equidistant from B(-3,1) and F(8,-2). Find the coordinates of P.
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Algebra.Com's Answer #535612 by Theo(13342)\"\" \"About 
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the point P is equal to (a,b) where b is equal to 2 * a.
\n" ); document.write( "the point P can therefore be represented as (a,2a).\r
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\n" ); document.write( "\n" ); document.write( "the point P is equidistant from the points B(-3,1) and F(8,-2)
\n" ); document.write( "this means that the length of the line between P and B is equal to the length of the line between P and F.\r
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\n" ); document.write( "\n" ); document.write( "the equation for the length of a line is:
\n" ); document.write( "L = sqrt((x2-x1)^2 + (y2-y1)^2)\r
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\n" ); document.write( "\n" ); document.write( "Assign one the points for each line to (x1,y1) and assign the other point for each line to (x2,y2)\r
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\n" ); document.write( "\n" ); document.write( "for the first line, you get:
\n" ); document.write( "(x1,y1) = (-3,1)
\n" ); document.write( "(x2,y2) = (a,2a)\r
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\n" ); document.write( "\n" ); document.write( "for the second line, you get:
\n" ); document.write( "(x1,y1) = (8,-2)
\n" ); document.write( "(x2,y2) = (a,2a)\r
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\n" ); document.write( "\n" ); document.write( "the point (x2,y2) is the point that's common to both lines.\r
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\n" ); document.write( "\n" ); document.write( "for each line you want to find the length of the line.\r
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\n" ); document.write( "\n" ); document.write( "for the first line, the equation for L becomes:\r
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\n" ); document.write( "\n" ); document.write( "L1 = sqrt((a+3)^2 + (2a-1)^2)\r
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\n" ); document.write( "\n" ); document.write( "for the second line, the equation for L becomes:\r
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\n" ); document.write( "\n" ); document.write( "L2 = sqrt((a-8)^2 + (2a+2)^2)\r
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\n" ); document.write( "\n" ); document.write( "simplify both these equations to get:\r
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\n" ); document.write( "\n" ); document.write( "L1 = sqrt(2a^2 + 6a + 9 + 4a^2 - 4a + 1)
\n" ); document.write( "L2 = sqrt(2a^2 - 16a + 64 + 4a^2 + 8a + 4)\r
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\n" ); document.write( "\n" ); document.write( "simplify these equation further to get:\r
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\n" ); document.write( "\n" ); document.write( "L1 = sqrt(6a^2 + 2a + 10)
\n" ); document.write( "L2 = sqrt(6a^2 - 8a + 68)\r
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\n" ); document.write( "\n" ); document.write( "set these equations equal to each other to get:\r
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\n" ); document.write( "\n" ); document.write( "sqrt(6a^2 + 2a + 10) = sqrt(6a^2 - 8a + 68\r
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\n" ); document.write( "\n" ); document.write( "square both sides of this equation to get:\r
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\n" ); document.write( "\n" ); document.write( "6a^2 + 2a + 10 = 6a^2 - 8a + 68\r
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\n" ); document.write( "\n" ); document.write( "solve for a to get:\r
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\n" ); document.write( "\n" ); document.write( "a = 5.8
\n" ); document.write( "2a = 11.6\r
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\n" ); document.write( "\n" ); document.write( "those are your solutions for a and 2a and those are the x and y coordinates for point P.\r
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\n" ); document.write( "\n" ); document.write( "your 2 lines are:\r
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\n" ); document.write( "\n" ); document.write( "L1 = the line between the points (-3,1) and (5.8,11.6)
\n" ); document.write( "L2 = the line between the points (8,-2) and (5.8,11.6)\r
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\n" ); document.write( "\n" ); document.write( "to confirm the lengths of these lines are equal, then solve for the lengths of both lines.\r
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\n" ); document.write( "\n" ); document.write( "you will find that:\r
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\n" ); document.write( "\n" ); document.write( "length of L1 is equal to sqrt(189.8)
\n" ); document.write( "length of L2 is equal to sqrt(189.8)\r
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