document.write( "Question 993749: Find point P(x,y) on line y=2x-1 so that its distance from point Q(4,3) is 2 \n" ); document.write( "
Algebra.Com's Answer #613019 by Theo(13342)\"\" \"About 
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you can solve this graphically easy enough if you have good graphing software.
\n" ); document.write( "using one, i found that two points satisfy the requirements.
\n" ); document.write( "those points are (2,3) and (2.8,4.60)\r
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\n" ); document.write( "\n" ); document.write( "what you are looking for on the graph is the intersection of the line y = 2x-1 with the intersection of the circle whose equation is (x-4)^2 + (y-3)^2 = 4.\r
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\n" ); document.write( "\n" ); document.write( "without graphing software it's not quite as easy, but can be done.\r
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\n" ); document.write( "\n" ); document.write( "you are still looking for the intersection of the graph of the equations shown above, but you have to do it algebraically.\r
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\n" ); document.write( "\n" ); document.write( "you have 2 equations:\r
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\n" ); document.write( "\n" ); document.write( "y = 2x - 1
\n" ); document.write( "(x-4)^2 + (y-3)^2 = 4\r
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\n" ); document.write( "\n" ); document.write( "the equation of y = 2x - 1 is a straight line.\r
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\n" ); document.write( "\n" ); document.write( "the equation of (x-4)^2 + (y-3)^2 = 4 is a circle whose center is (4,3) and whose radius is 2.\r
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\n" ); document.write( "\n" ); document.write( "replace y in the second equation with the value of y from the first equation to get:\r
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\n" ); document.write( "\n" ); document.write( "(x-4)^2 + (2x-1-3)^2 = 4\r
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\n" ); document.write( "\n" ); document.write( "simplify to get:\r
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\n" ); document.write( "\n" ); document.write( "(x-4)^2 + (2x-4)^2 = 4\r
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\n" ); document.write( "\n" ); document.write( "simplify the equation to get:\r
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\n" ); document.write( "\n" ); document.write( "x^2 - 8x + 16 + 4x^2 - 16x + 16 = 4\r
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\n" ); document.write( "\n" ); document.write( "combine like terms to get:\r
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\n" ); document.write( "\n" ); document.write( "5x^2 - 24x + 32 = 4\r
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\n" ); document.write( "\n" ); document.write( "subtract 4 from both sides of the equation to get:\r
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\n" ); document.write( "\n" ); document.write( "5x^2 - 24x + 28 = 0\r
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\n" ); document.write( "\n" ); document.write( "use the quadratic formula to find the values of x that satisfy that equation.\r
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\n" ); document.write( "\n" ); document.write( "you will find that the values of x = 2 and x = 2.8 satisfy both equations and are therefore intersections of both equations on the graph.\r
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\n" ); document.write( "\n" ); document.write( "when x = 2, y = 2x-1 becomes y = 3.
\n" ); document.write( "when x = 2.8, y = 2x-1 becomes 4.6.\r
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\n" ); document.write( "\n" ); document.write( "the points on the circle that are also on the line are therefore (2,3) and (2.8,4.6)\r
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\n" ); document.write( "\n" ); document.write( "both these points should be 2 units away from the center of the circle because the line segments formed by each of these points and the center of the circle is a radius of the circle.\r
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\n" ); document.write( "\n" ); document.write( "the distance between two points on the graph is given by the equation:\r
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\n" ); document.write( "\n" ); document.write( "d = sqrt((x1-x2)^2 + (y1-y2)^2).\r
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\n" ); document.write( "\n" ); document.write( "the distance between (2,3) and (4,3) is equal to sqrt((4-2)^2 + (3-3)^2) which is equal to sqrt(2^2) which is equal to sqrt(4) which is equal to 2.\r
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\n" ); document.write( "\n" ); document.write( "the distance between (2.8,4.6) and (4,3) is equal to sqrt((4-2.8)^2 + (3-4.6)^2) which is equal to sqrt(1.2)^2 + (-1.6)^2) which is equal to sqrt(1.44 + 2.56) which is equal to sqrt(4) which is equal to 2.\r
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\n" ); document.write( "\n" ); document.write( "either one of these points will satisfy the requirements of this problem.\r
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\n" ); document.write( "\n" ); document.write( "the graph of the line and the circle are shown below:\r
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