document.write( "Question 1183956: If 4M+N=20 and N+P=20, what is the value of M?
\n" ); document.write( "A.0
\n" ); document.write( "B.4
\n" ); document.write( "C.16
\n" ); document.write( "D.24
\n" ); document.write( "E.It cannot be determined from the information given.
\n" ); document.write( "The correct answer was E but I don't know how so can you explain? Thank you. \n" ); document.write( "

Algebra.Com's Answer #814473 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
If 4M+N=20 and N+P=20, what is the value of M?
\n" ); document.write( "A.0
\n" ); document.write( "B.4
\n" ); document.write( "C.16
\n" ); document.write( "D.24
\n" ); document.write( "E.It cannot be determined from the information given.
\n" ); document.write( "The correct answer was E but I don't know how so can you explain? Thank you.
\n" ); document.write( "~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

\r\n" );
document.write( "You are given 2 equations for 3 variables\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    4M + N     = 20     (1)\r\n" );
document.write( "\r\n" );
document.write( "         N + P = 20     (2)\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "From the second equation, express N = 20-P  and substitute it into equation (1), replacing N there.  You will get\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    4M + (20-P) = 20,\r\n" );
document.write( "\r\n" );
document.write( "or\r\n" );
document.write( "\r\n" );
document.write( "    4M = P.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "So, M  may have  ANY VALUE,  depending on the value of P, which is not given.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "     THEREFORE, the answer to the problem question is option E.      ANSWER\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Notice that you have only two linear equations for three unknowns.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "At these conditions, the system is underdetermined and have MANY solutions (more than one).\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "It explains the situation from the general point of view.\r\n" );
document.write( "

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

\n" );