document.write( "Question 992821: Hi, I need help solving this : Find the point (x, y) on the line y=x that is equidistant from the points (8, 9) and (1, -10), thank you! \n" ); document.write( "
Algebra.Com's Answer #612321 by Theo(13342)![]() ![]() You can put this solution on YOUR website! you want to find the point on the line y = x that is the same distance from the points (8,9) and (1,-10).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that point will be (x,y) = (22/26, 22/26)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the following graph shows you where that point lies on the graph.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here's how you find it.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you need to find the equation of the line between the points (8,9) and (1,-10).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the equation of that line is y = 19/7 * x - 89/7.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you then need to find the midpoint of that line.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the midpoint of that line is (4.5, -1/2).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you then need to find the equation of a line perpendicular to the line of y = 19/7 * x - 89/7 and passing through the point (4.5, -1/2).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the equation of that line is y = -7/19 * x + 22/19.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that line is perpendicular to the line y = 19/7 * x - 89/7 because it's slope is the negative reciprocal of the slope of that line.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "it doesn't look like it's perpendicular on the graph because i forgot to square the axes to make it look like what it is.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i'll correct that and show it to you again below after it's been squared.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that perpendicular line is the perpendicular bisector of the original line of y = 19/7 * x - 89/7.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "any point on that line will be equidistant from the end points of that original line.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since that point needs to also intersect the line y = x, you need to find the intersection of the line y = x with the line y = -7/19 * x + 22/19.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that point is (22/26,22/26).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on the graph that shows up as .846 rounded to 3 decimal places, or .85 rounded to two decimal places.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "following is the picture of the same graph after it was squared. \n" ); document.write( "this picture clearly shows the perpendicularity.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i calculated the distance between the point (22/26,22/26) and the points (8,9) and (1,-10) and confirmed that the distances are the same.\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |