document.write( "Question 320138: The sum of a number and it's reciprocal is 10/3. What is the number ? \n" ); document.write( "
Algebra.Com's Answer #229279 by CharlesG2(834) ![]() You can put this solution on YOUR website! The sum of a number and it's reciprocal is 10/3. What is the number ?\r \n" ); document.write( "\n" ); document.write( "let x = the number \n" ); document.write( "let 1/x = the reciprocal of the number\r \n" ); document.write( "\n" ); document.write( "x + 1/x = 10/3 \n" ); document.write( "x^2 + 1 = (10/3)x (multiplied both sides by x) \n" ); document.write( "x^2 - (10/3)x = -1 \n" ); document.write( "x^2 - (10/3)x + (-5/3)^2 = -1 + (-5/3)^2 (completed the square) \n" ); document.write( "(x - 5/3)(x - 5/3) = x^2 - (5/3)x - (5/3)x + (-5/3)^2 (by use of FOIL) \n" ); document.write( "(x - 5/3)^2 = -1 + 25/9 = -9/9 + 25/9 = 16/9 \n" ); document.write( "x - 5/3 = 4/3 \n" ); document.write( "x = 9/3 = 3 \n" ); document.write( "its reciprocal 1/x = 1/3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |