document.write( "Question 148484: Solve using addition and multiplication principals.\r
\n" ); document.write( "\n" ); document.write( "5 + 4x < 21
\n" ); document.write( "The solution set is {x/x ??}\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Solve the following system of equation\r
\n" ); document.write( "\n" ); document.write( "x + 4y = 2 (1)
\n" ); document.write( "x = 7 -4y (2)
\n" ); document.write( "What is the soltution of the system? \n" ); document.write( "

Algebra.Com's Answer #108815 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
Solve using addition and multiplication principals.
\n" ); document.write( "5 + 4x < 21
\n" ); document.write( "The solution set is {x/x ??} \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"5%2B4x%3C21\"$ Start with the given inequality.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"4x%3C21-5\"$ Subtract $\"5\"$ from both sides.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"4x%3C16\"$ Combine like terms on the right side.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"x%3C%2816%29%2F%284%29\"$ Divide both sides by $\"4\"$ to isolate $\"x\"$ . \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"x%3C4\"$ Reduce.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "----------------------------------------------------------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Answer:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the answer is $\"x%3C4\"$ \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the solution set is

\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Which in interval notation is

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

\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Solve the following system of equation \r
\n" ); document.write( "\n" ); document.write( "x + 4y = 2 (1)
\n" ); document.write( "x = 7 -4y (2)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Start with the given system\r
\n" ); document.write( "\n" ); document.write( " $\"x%2B4y=2\"$
\n" ); document.write( " $\"x=7-4y\"$ \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"7-4y%2B4y=2\"$ Plug in $\"x=7-4y\"$ into the first equation. In other words, replace each $\"x\"$ with $\"7-4y\"$ . Notice we've eliminated the $\"x\"$ variables. So we now have a simple equation with one unknown.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"7=2\"$ Combine like terms on the left side\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"0=2-7\"$ Subtract 7 from both sides\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"0=-5\"$ Combine like terms on the right side\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Since this equation is never true for any y value, this means there are no solutions.
\n" ); document.write( " \n" ); document.write( "

\n" );