document.write( "Question 110097This question is from textbook algebra 1
\n" ); document.write( ": 7)
\n" ); document.write( "y=6-x
\n" ); document.write( "2x-3y=22 \r
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\n" ); document.write( "\n" ); document.write( "13)
\n" ); document.write( "4x+5y=5
\n" ); document.write( "6x+7y=7
\n" ); document.write( " \r
\n" ); document.write( "\n" ); document.write( "15)
\n" ); document.write( "x+9y=4
\n" ); document.write( "2x+3y=7 \n" ); document.write( "

Algebra.Com's Answer #80212 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
7)
\n" ); document.write( " $\"y=6-x+\"$ .....substitute $\"y\"$ in second expression
\n" ); document.write( " $\"2x-3y=22+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"2x+-3%286+-+x%29=+22+\"$
\n" ); document.write( " $\"2x+-18+%2B+6x=+22+\"$
\n" ); document.write( " $\"8x+-18+=+22+\"$ ....move $\"-18\"$ to the right
\n" ); document.write( " $\"8x+=+22+%2B+18+\"$
\n" ); document.write( " $\"8x+=+40+\"$ ..divide both sides by $\"8\"$
\n" ); document.write( " $\"x+=+5+\"$
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\n" ); document.write( "now find $\"y\"$
\n" ); document.write( " $\"y=6-x+\"$
\n" ); document.write( " $\"y=6-5+\"$
\n" ); document.write( " $\"y=+1+\"$ \r
\n" ); document.write( "\n" ); document.write( "13) \r
\n" ); document.write( "\n" ); document.write( " $\"4x%2B5y=5\"$ ....both sides multiply by $\"6\"$
\n" ); document.write( " $\"6x%2B7y=7\"$ ....both sides multiply by $\"-4\"$
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\n" ); document.write( " $\"24x%2B30y=30\"$
\n" ); document.write( " $\"-24x-28y=-28\"$ ......now add them\r
\n" ); document.write( "\n" ); document.write( " $\"24x+%2B%28-24x%29+%2B+30y+%2B%28-28y%29+=+30+%2B+%28-28%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"2y+=+2\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"y+=+1\"$ \r
\n" ); document.write( "\n" ); document.write( "then find $\"x\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4x%2B5y=5\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4x+%2B+5%2A1+=+5\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4x+=+5+-+5\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4x+=+0\"$ ........since $\"4\"$ is $\"not_+equal_+to_0\"$ , then $\"x_must_be_=+0\"$ \r
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\n" ); document.write( "\n" ); document.write( "15)\r
\n" ); document.write( "\n" ); document.write( " $\"x%2B9y=4\"$ ...both sides in this equation multiply by $\"-2\"$
\n" ); document.write( " $\"2x%2B3y=7\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-2x-+18y=-8\"$ ....... add both equations
\n" ); document.write( " $\"2x%2B3y=7\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-2x+%2B2x+-18y+%2B+3y+=-8+%2B+7\"$
\n" ); document.write( " $\"-15y+=+-+1\"$
\n" ); document.write( " $\"y+=+-1%2F-15\"$
\n" ); document.write( " $\"y+=+1%2F15\"$ \r
\n" ); document.write( "\n" ); document.write( "then find $\"x\"$
\n" ); document.write( " $\"x%2B9y=4\"$
\n" ); document.write( " $\"x%2B9%281%2F15%29=4\"$ ...
\n" ); document.write( " $\"x%2B9%2F15=4\"$ ...
\n" ); document.write( " $\"x%2B%289%3A3%29%2F%2815%3A3%29=4\"$ ...
\n" ); document.write( " $\"x%2B3%2F5=4\"$ .........move $\"3%2F5\"$ to the right
\n" ); document.write( " $\"x+=+4+-+3%2F5\"$
\n" ); document.write( " $\"x+=+20%2F5+-+3%2F5\"$
\n" ); document.write( " $\"x+=+17%2F5\"$
\n" ); document.write( " $\"x+=+3%282%2F5%29\"$ \r
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