document.write( "Question 258389: Determine the shortest distance from (9,5) to 5x + 3y =15 \n" ); document.write( "
Algebra.Com's Answer #190224 by stanbon(75887) ![]() You can put this solution on YOUR website! Determine the shortest distance from (9,5) to 5x + 3y =15 \n" ); document.write( "--------------------------- \n" ); document.write( "The shortest distance is a perpendicular distance. \n" ); document.write( "--- \n" ); document.write( "Find the slope of the given line: \n" ); document.write( "y = (-5/3)x + 5 \n" ); document.write( "--- \n" ); document.write( "ANY line perpendicular to that line must \n" ); document.write( "have a slope = 3/5 \n" ); document.write( "-------------------------- \n" ); document.write( "Find the equation of the line with slope = 3/5 and passing thru (9,5): \n" ); document.write( "5 = (3/5)9 + b \n" ); document.write( "5 = (27/5) + b \n" ); document.write( "b = (25/5)-(27/5) \n" ); document.write( "b = -2/5 \n" ); document.write( "======================== \n" ); document.write( "Equation you want: y = (3/5)x - (2/5) \n" ); document.write( "5y = 3x - 2 \n" ); document.write( "3x - 5y = 2 \n" ); document.write( "======================== \n" ); document.write( "Find the point of intersection of the two equations: \n" ); document.write( "3x-5y = 2 \n" ); document.write( "5x+3y = 15 \n" ); document.write( "---- \n" ); document.write( "Multiply 1st Eq. by 3; Multiply 2nd equation by 5: \n" ); document.write( "9x - 15y = 6 \n" ); document.write( "25x- 15y = 75 \n" ); document.write( "----------------------- \n" ); document.write( "Add and solve for \"x\": \n" ); document.write( "34x = 81 \n" ); document.write( "x = 81/34 \n" ); document.write( "-- \n" ); document.write( "Substitute to solve for \"y\": \n" ); document.write( "3(81/34) - 5y = 6 \n" ); document.write( "243/34 - 5y = 6 \n" ); document.write( "5y = (243-204)/34 \n" ); document.write( "5y = 39/34 \n" ); document.write( "y = (39/170) \n" ); document.write( "------------- \n" ); document.write( "The point of intersection is (81/34 , 39/170) \n" ); document.write( "------------------- \n" ); document.write( "Find the distance between that point and (9,5) \n" ); document.write( "================================================ \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |