document.write( "Question 751189: Please help with these.
\n" ); document.write( "Determine whether each set of ordered pairs is a function.
\n" ); document.write( "1. (4,1)(3,2)(2,3)(1,8)
\n" ); document.write( "2. (1,3)(2,3)(3,3)(4,3)
\n" ); document.write( "3. (1,1)(2,2)(3,3)(4,4)
\n" ); document.write( "4. (2,1)(4,2)(5,3)(-2,4)
\n" ); document.write( "5. (8,1)(8,2)(8,3)(8,4)
\n" ); document.write( "6. (-2,-2)(0,0)(6,6)(-8,-8)\r
\n" ); document.write( "\n" ); document.write( "thank you for your help.
\n" ); document.write( " \n" ); document.write( "
Algebra.Com's Answer #457037 by Edwin McCravy(20067)\"\" \"About 
You can put this solution on YOUR website!
\r\n" );
document.write( "A set of ordered pairs form a function if all the\r\n" );
document.write( "x-coordinates (first coordinates) are different,\r\n" );
document.write( "and no two are the same.  It doesn't matter if some\r\n" );
document.write( "or all of the y-coordinates or second coordinates are\r\n" );
document.write( "the same.\r\n" );
document.write( "\r\n" );
document.write( "1. (4,1)(3,2)(2,3)(1,8)\r\n" );
document.write( "\r\n" );
document.write( "That is a function because all four x-values, that is,\r\n" );
document.write( "x-coordinates, or first coordinates, 4,3,2,1 are all \r\n" );
document.write( "different.\r\n" );
document.write( "\r\n" );
document.write( "2. (1,3)(2,3)(3,3)(4,3)\r\n" );
document.write( "\r\n" );
document.write( "That is a function because all four x-values, that is,\r\n" );
document.write( "first coordinates, 1,2,3,4 are all different. \r\n" );
document.write( "\r\n" );
document.write( "[Notice there that it doesn't matter that the y-values, \r\n" );
document.write( "that is, second coordinates, 3,3,3,3 are the same.  Only \r\n" );
document.write( "the x-values, or first coordinates must be different in \r\n" );
document.write( "order to have a function.\r\n" );
document.write( "\r\n" );
document.write( "3. (1,1)(2,2)(3,3)(4,4)\r\n" );
document.write( "\r\n" );
document.write( "That is a function because all four x-values, that is,\r\n" );
document.write( "first coordinates, 1,2,3,4 are all different. \r\n" );
document.write( "\r\n" );
document.write( "4. (2,1)(4,2)(5,3)(-2,4)\r\n" );
document.write( "\r\n" );
document.write( "That is a function because all four x-values, that is,\r\n" );
document.write( "first coordinates, 2,4,5,-2 are all different.\r\n" );
document.write( "\r\n" );
document.write( "5. (8,1)(8,2)(8,3)(8,4)\r\n" );
document.write( "\r\n" );
document.write( "That is NOT a function because all four x-values, that is,\r\n" );
document.write( "first coordinates, 8,8,8,8 are NOT all different.\r\n" );
document.write( "\r\n" );
document.write( "6. (-2,-2)(0,0)(6,6)(-8,-8) \r\n" );
document.write( "\r\n" );
document.write( "That is a function because all four x-values, that is,\r\n" );
document.write( "first coordinates, -2,0,6,-8 are all different\r\n" );
document.write( "\r\n" );
document.write( "Edwin

\n" ); document.write( " \n" ); document.write( "
\n" );