document.write( "Question 755490: Find the distance from (6,-1) to the line defined by y=2x-3. Please Help!!!! \n" ); document.write( "
Algebra.Com's Answer #459761 by Cromlix(4381) You can put this solution on YOUR website! The line that is perpendicular to \n" ); document.write( "y = 2x - 3 has a gradient of -1/2 \n" ); document.write( "For lines perpendicular to each other \n" ); document.write( "their gradients multiply together to \n" ); document.write( "give -1 \n" ); document.write( "(m1 x m2 = -1) \n" ); document.write( "Using the formula y -b =m(x - a) \n" ); document.write( "with m = -1/2 and coordinates (6, -1) \n" ); document.write( "y - (-1) = -1/2(x - 6) \n" ); document.write( " y + 1 = -1/2x + 3 \n" ); document.write( " y = -1/2x + 3 - 1 \n" ); document.write( " y = -1/2x + 2 \n" ); document.write( "OR 2y = -x + 4 \n" ); document.write( " To find where line 2y = -x + 4 \n" ); document.write( "and y = 2x - 3 meet, set out and \n" ); document.write( "solve simultaneous equations:-\r \n" ); document.write( "\n" ); document.write( " 2y + x = +4....1 \n" ); document.write( " y -2x = -3.....2 \n" ); document.write( "Multiply (1) by 2 \n" ); document.write( " 4y + 2x = 8 \n" ); document.write( " y - 2x = -3 \n" ); document.write( "Add \n" ); document.write( " 5y = 5 \n" ); document.write( " y = 1 \n" ); document.write( "Substitute y = 1 into Eq. 2 \n" ); document.write( " y - 2x = - 3 \n" ); document.write( " 1 - 2x = - 3 \n" ); document.write( " - 2x = - 3 - 1 \n" ); document.write( " - 2x = -4 \n" ); document.write( " x = 2 \n" ); document.write( "So, this is the point where the lines meet.\r \n" ); document.write( "\n" ); document.write( "Distance from (6, -1) and (1,2) \n" ); document.write( "Square root((x2 - x1)^2 + (y2 - y1)^2) \n" ); document.write( "Square root ( (1 - 6)^2 + (2 - (-1))^2) \n" ); document.write( "Square root (5^2 + 3^2) \n" ); document.write( " Square root(34) \n" ); document.write( " = 5.8 units \n" ); document.write( " |