document.write( "Question 826893: Which option is correct?
\n" ); document.write( "5 , ? , 4 , 7.5 , 17 , 45\r
\n" ); document.write( "\n" ); document.write( "A. 3.5
\n" ); document.write( "B. 3
\n" ); document.write( "C. 2.5
\n" ); document.write( "D. 2 \n" ); document.write( "
Algebra.Com's Answer #498362 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
\r\n" );
document.write( "5, ?, 4, 7.5, 17, 45\r\n" );
document.write( "\r\n" );
document.write( "Let x be the missing number\r\n" );
document.write( "\r\n" );
document.write( "5, x, 4, 7.5, 17, 45\r\n" );
document.write( "\r\n" );
document.write( "List all 6 terms in a column\r\n" );
document.write( "  \r\n" );
document.write( " 5                                                                           \r\n" );
document.write( " x                                                                         \r\n" );
document.write( " 4                                             \r\n" );
document.write( " 7.5                             \r\n" );
document.write( "17                   \r\n" );
document.write( "45\r\n" );
document.write( "\r\n" );
document.write( "Subtract each number or expression from the one immediately\r\n" );
document.write( "underneath it, write it out beside that number in a new column\r\n" );
document.write( "and simplify, if necessary\r\n" );
document.write( "\r\n" );
document.write( " 5    x-5                                                                     \r\n" );
document.write( " x    4-x                                                                \r\n" );
document.write( " 4    7.5-4=3.5                                  \r\n" );
document.write( " 7.5  17-7.5=9.5               \r\n" );
document.write( "17    45-17=28\r\n" );
document.write( "45\r\n" );
document.write( "\r\n" );
document.write( "Make a third column the same way\r\n" );
document.write( "\r\n" );
document.write( " 5    x-5        (4-x)-(x-5)=9-2x                                             \r\n" );
document.write( " x    4-x        3.5-(4-x)=x-.5                                          \r\n" );
document.write( " 4    7.5-4=3.5  9.5-3.5=6                    \r\n" );
document.write( " 7.5  17-7.5=9.5 28-9.5=18.5\r\n" );
document.write( "17    45-17=28\r\n" );
document.write( "45\r\n" );
document.write( "\r\n" );
document.write( "Make more columns the same way.  Continue until there are just two\r\n" );
document.write( "in the last column\r\n" );
document.write( "\r\n" );
document.write( " 5    x-5        (4-x)-(x-5)=9-2x (x-.5)-(9-2x)=3x-9.5 (6.5-x)-(3x-9.5)=16-4x\r\n" );
document.write( " x    4-x        3.5-(4-x)=x-.5   6-(x-.5)=6.5-x       12.5-(6.5-x)=6+x\r\n" );
document.write( " 4    7.5-4=3.5  9.5-3.5=6        18.5-6=12.5\r\n" );
document.write( " 7.5  17-7.5=9.5 28-9.5=18.5\r\n" );
document.write( "17    45-17=28\r\n" );
document.write( "45\r\n" );
document.write( "\r\n" );
document.write( "Set the two expressions in the last column equal to each other:\r\n" );
document.write( "\r\n" );
document.write( "16-4x = 6+x\r\n" );
document.write( "   10 = 5x\r\n" );
document.write( "    2 = x \r\n" );
document.write( "\r\n" );
document.write( "The missing number is 2.\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" ); document.write( "
\n" );