document.write( "Question 428063: I am supposed to solve using the substitution method.
\n" ); document.write( "5x-6y=-20
\n" ); document.write( "5x+45=y
\n" ); document.write( "Here is what I have tried and I think it is wrong.
\n" ); document.write( "I switched the 2nd equation so that it read y=5x+45.
\n" ); document.write( "It was then,
\n" ); document.write( "5x-6y=-20
\n" ); document.write( "y=5x+45
\n" ); document.write( "Here is how I worked it out
\n" ); document.write( "5x-6(5x+45)=-20
\n" ); document.write( "5x-30x-270=-20
\n" ); document.write( "-35x-270+270=-20+270
\n" ); document.write( "-35x=250 and I divided both sides by -35 and got 7.14 but I know this is wrong and I do not know where or what I did wrong. \n" ); document.write( "

Algebra.Com's Answer #297601 by mananth(16946) $\"\"$ $\"About$

You can put this solution on YOUR website!
5x-6y=-20
\n" ); document.write( "5x+45=y\r
\n" ); document.write( "\n" ); document.write( "5x-6y=-20 .............1
\n" ); document.write( "y=45+5x ---------2
\n" ); document.write( "plug the value of y in (1)
\n" ); document.write( "5x-6(45+ 5x)=-20
\n" ); document.write( "5x-270-30x=-20
\n" ); document.write( "5x-30x=-20+270
\n" ); document.write( "-25x=250
\n" ); document.write( "/-25
\n" ); document.write( "x=-10
\n" ); document.write( "Plug the value of x in (1)
\n" ); document.write( "5x-6y=-20
\n" ); document.write( "5*-10-6y =-20
\n" ); document.write( "-50-6y=-20
\n" ); document.write( "-6y=30
\n" ); document.write( "/-6
\n" ); document.write( "y=-5
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "y=45+5x
\n" ); document.write( "-5=45-50
\n" ); document.write( " \n" ); document.write( "

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