document.write( "Question 1050872: What 2 numbers add to get \"1\" and multiply to get \"5\"? \n" ); document.write( "
Algebra.Com's Answer #666489 by rothauserc(4718)![]() ![]() You can put this solution on YOUR website! 1) x + y = 1 \n" ); document.write( ": \n" ); document.write( "2) x * y = 5 \n" ); document.write( ": \n" ); document.write( "solve equation 1) for x \n" ); document.write( ": \n" ); document.write( "x = 1 - y \n" ); document.write( ": \n" ); document.write( "substitute for x in equation 2) \n" ); document.write( ": \n" ); document.write( "(1 - y) * y = 5 \n" ); document.write( ": \n" ); document.write( "y - y^2 = 5 \n" ); document.write( ": \n" ); document.write( "y^2 -y +5 = 0 \n" ); document.write( ": \n" ); document.write( "solve for y by completing the square \n" ); document.write( ": \n" ); document.write( "y^2 -y = -5 \n" ); document.write( ": \n" ); document.write( "y^2 -y +(1/4) = -5 +(1/4) \n" ); document.write( ": \n" ); document.write( "(y - (1/2))^2 = -19/4 \n" ); document.write( ": \n" ); document.write( "y -(1/2) = square root(-19/4) = (i * square root(19))/2 \n" ); document.write( ": \n" ); document.write( "********************************** \n" ); document.write( "y = (1 + i * square root(19)) / 2 \n" ); document.write( "y = (1 - i * square root(19)) / 2 \n" ); document.write( "********************************** \n" ); document.write( ": \n" ); document.write( "*********************************************************************** \n" ); document.write( "x = 1 - ((1 + i * square root(19)) / 2) = (1 - i * square root(19)) / 2 \n" ); document.write( "x = 1 - ((1 - i * square root(19)) / 2) = (1 + i * square root(19)) / 2 \n" ); document.write( "*********************************************************************** \n" ); document.write( ": \n" ); document.write( "we have two sets of solutions \n" ); document.write( ": \n" ); document.write( "********************************** \n" ); document.write( "x = (1 - i * square root(19)) / 2 \n" ); document.write( "y = (1 + i * square root(19)) / 2 \n" ); document.write( ": \n" ); document.write( "x = (1 + i * square root(19)) / 2 \n" ); document.write( "y = (1 - i * square root(19)) / 2 \n" ); document.write( "********************************** \n" ); document.write( ": \n" ); document.write( "checking answers \n" ); document.write( ": \n" ); document.write( "clearly x + y = 1 \n" ); document.write( ": \n" ); document.write( "what about xy = 5 \n" ); document.write( ": \n" ); document.write( "xy = (1 -(i^2 * 19)) / 4 = (1 - (-19)) / 4 = 20 / 4 = 5 \n" ); document.write( ": \n" ); document.write( "our answers check :-) \n" ); document.write( ":\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |