document.write( "Question 182618: Please Help.
\n" ); document.write( "Use elimination to solve each system of equations.
\n" ); document.write( "7M+4N=2 7M+2N=8 \n" ); document.write( "

Algebra.Com's Answer #137158 by jojo14344(1513) $\"\"$ $\"About$

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\n" ); document.write( "Given:
\n" ); document.write( " $\"7M%2B4N=2\"$ --------> EQN 1
\n" ); document.write( " $\"7M%2B2N=8\"$ --------> EQN 2
\n" ); document.write( "Let $\"system%28M=highlight%28x%29%2CN=highlight%28y%29%29\"$
\n" ); document.write( "Multiply EQN 2 by 2 and subtract from EQN 1:
\n" ); document.write( "EQN 2, (7x+2y=8)(2)= $\"14x%2B4y=16\"$
\n" ); document.write( "Then,
\n" ); document.write( "7x+4y=2, EQN 1
\n" ); document.write( "-(14x+4y=16), New EQN 2 * remember to change signs
\n" ); document.write( "------------
\n" ); document.write( " $\"-7x=-14\"$ ------> $\"cross%28-7%29x%2Fcross%28-7%29=cross%28-14%292%2Fcross%28-7%29\"$
\n" ); document.write( " $\"highlight%28x=2=M%29\"$ , subst. in NEW EQN 2:
\n" ); document.write( " $\"14%2A2%2B4y=16\"$
\n" ); document.write( " $\"4y=16-28=-12\"$ --------> $\"cross%284%29y%2Fcross%284%29=cross%28-12%293%2Fcross%284%29\"$
\n" ); document.write( " $\"highlight%28y=-3=N%29\"$
\n" ); document.write( "It shows, both eqns will meet at point (2,-3):
\n" ); document.write( "------>RED>>>> EQN 1; GREEN>>> EQN 2
\n" ); document.write( "Thank you,
\n" ); document.write( "Jojo
\n" ); document.write( " \n" ); document.write( "

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