document.write( "Question 656751: How do you determine if y is a function of x in: y^2=7x \n" ); document.write( "
Algebra.Com's Answer #409624 by Edwin McCravy(20056)![]() ![]() You can put this solution on YOUR website! \r\n" ); document.write( "y² = 7x\r\n" ); document.write( "\r\n" ); document.write( "It is not a function because, for instance,\r\n" ); document.write( "\r\n" ); document.write( "(7,7) and (7,-7) are both solutions, since:\r\n" ); document.write( "\r\n" ); document.write( "(7)² = 7(7)\r\n" ); document.write( " 49 = 49\r\n" ); document.write( "\r\n" ); document.write( "But also\r\n" ); document.write( "\r\n" ); document.write( "(-7)² = 7(7)\r\n" ); document.write( " 49 = 49\r\n" ); document.write( "\r\n" ); document.write( "In a function the same value of x cannot correspond \r\n" ); document.write( "to two different values of y.\r\n" ); document.write( "\r\n" ); document.write( "However, (7,7) and (7,-7) have the same x-values \r\n" ); document.write( "but different y-values.\r\n" ); document.write( "\r\n" ); document.write( "Also the graph of y² = 7x is this:\r\n" ); document.write( "\r\n" ); document.write( "\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |