document.write( "Question 174464This question is from textbook Algebra 2, Texas Edition
\n" ); document.write( ": Identify three methods you can use to solve a sysytiem of equations and explain when to use each method then write example systems that illustrate when to use each method. \n" ); document.write( "
Algebra.Com's Answer #129461 by checkley77(12844)\"\" \"About 
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SUBSTIUTION: USE WHEN ONE EQUATION HAS NO INTEGER.
\n" ); document.write( "Y=3X
\n" ); document.write( "2Y-8=2X
\n" ); document.write( "2*3X-8=2X
\n" ); document.write( "6X-8-2X=0
\n" ); document.write( "4X=8
\n" ); document.write( "X=8/4
\n" ); document.write( "X=2 ANS.
\n" ); document.write( "Y=3*2
\n" ); document.write( "Y=6 ANS.
\n" ); document.write( "PROOF:
\n" ); document.write( "2*6-8=2*4
\n" ); document.write( "12-8=4
\n" ); document.write( "4=4
\n" ); document.write( "-----------------------------
\n" ); document.write( "ADDITION: USE WHEN ONE UNKNOWN IS A MULTIPLE OF THE SAME UNKNOWN IN THE OTHER EQUATION.
\n" ); document.write( "Y-3X=0 MULTIPLY THIS EQUATION BY -2 & ADD
\n" ); document.write( "2Y-2X=8
\n" ); document.write( "-2Y+6X=0
\n" ); document.write( "2Y-2X=8
\n" ); document.write( "----------
\n" ); document.write( "4X=8
\n" ); document.write( "X=8/4
\n" ); document.write( "X=2
\n" ); document.write( "Y-3*2=0
\n" ); document.write( "Y-6=0
\n" ); document.write( "Y=6
\n" ); document.write( "----------------
\n" ); document.write( "CROSS MULTIPLICATION: USE WHEN THERE ARE FRACTIONS INVOLVED.
\n" ); document.write( "Y/4X=3/4
\n" ); document.write( "4Y=12X
\n" ); document.write( "Y=12X/4
\n" ); document.write( "--------
\n" ); document.write( "3Y/3X=3
\n" ); document.write( "3(12X/4)/3X=3
\n" ); document.write( "(36X/4)/3X=3
\n" ); document.write( "36X/4=9X
\n" ); document.write( "36X=36X\r
\n" ); document.write( "
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