document.write( "Question 634643: solve the following system of equations
\n" ); document.write( "X – 3z = -5
\n" ); document.write( "2x- y + 2z= 16
\n" ); document.write( "7x – 3y -5z =19\r
\n" ); document.write( "\n" ); document.write( "can you walk me thru the steps please
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Algebra.Com's Answer #399796 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
solve the following system of equations
\n" ); document.write( "X – 3z = -5
\n" ); document.write( "2x- y + 2z= 16
\n" ); document.write( "7x – 3y -5z = 19
\n" ); document.write( "There is more than one way to solve this, but this is a pretty simple one.
\n" ); document.write( "A combination of substitution and elimination.
\n" ); document.write( ":
\n" ); document.write( "Rearrange the 1st equation to use for substitution:
\n" ); document.write( "x = (3z-5)
\n" ); document.write( ":
\n" ); document.write( "Multiply the 2nd equation by 3, subtract from the 3rd equation
\n" ); document.write( "7x – 3y - 5z = 19
\n" ); document.write( "6x - 3y + 6z = 48
\n" ); document.write( "-------------------
\n" ); document.write( "x + 0 - 11z = -29
\n" ); document.write( "Replace x with (3z-5) from the 1st equation
\n" ); document.write( "(3z-5) - 11z =-29
\n" ); document.write( "3z - 11z = -29 + 5
\n" ); document.write( "-8z = - 24
\n" ); document.write( "z = \"%28-24%29%2F%28-8%29\"
\n" ); document.write( "z = +3
\n" ); document.write( ":
\n" ); document.write( "Back to the 1st equation, replace z with 3
\n" ); document.write( "x = 3(3) - 5
\n" ); document.write( "x = 9 - 5
\n" ); document.write( "x = 4
\n" ); document.write( ":
\n" ); document.write( "Use the original 2nd equation to find y, Replace x and z
\n" ); document.write( "2x - y + 2z = 16
\n" ); document.write( "2(4) - y + 2(3) = 16
\n" ); document.write( "8 - y + 6 = 16
\n" ); document.write( "-y = 16 - 8 - 6
\n" ); document.write( "-y = 2
\n" ); document.write( "Y has to be positive, multiply both sides by -1
\n" ); document.write( "y = -2
\n" ); document.write( ":
\n" ); document.write( "Our Solution: x=4; y=-2; z=3
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\n" ); document.write( ":
\n" ); document.write( "Check these in the 3rd original equation
\n" ); document.write( "7x – 3y -5z = 19
\n" ); document.write( "7(4) - 3(-2) - 5(3) =
\n" ); document.write( "28 + 6 - 15 = 19; confirms our solutions
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