document.write( "Question 48523: Please help me solve this equation tutor 3x+y+13 and 3x+2y=17 using substitution \n" ); document.write( "
Algebra.Com's Answer #32115 by tutorcecilia(2152)\"\" \"About 
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3x+y=13 and 3x+2y=17
\n" ); document.write( "3x+y=13 [Pick one equation and solve for y (or x)]
\n" ); document.write( "3x-3x+y=13-3x
\n" ); document.write( "y=13-3x [Plug this back into the second equation for the \"y\"]
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\n" ); document.write( "3x+2(13-3x)=17 [Simplify]
\n" ); document.write( "3x+26-6x = 17
\n" ); document.write( "-3x+26=17 [Solve for x]
\n" ); document.write( "-3x+26-26=17-26
\n" ); document.write( "-3x=-9
\n" ); document.write( "-3x/-3=-9/-3
\n" ); document.write( "x=3
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\n" ); document.write( "3x+y=13 and 3x+2y=17
\n" ); document.write( "[Plug (x=3) back into the original equations to solve for y]
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\n" ); document.write( "3x+y=13
\n" ); document.write( "3(3)+y=13
\n" ); document.write( "9+y=13
\n" ); document.write( "y=13-9
\n" ); document.write( "y=4
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\n" ); document.write( "and
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\n" ); document.write( "3x+2y=17
\n" ); document.write( "3(3)+2y=17
\n" ); document.write( "9+2y=17
\n" ); document.write( "2y=8
\n" ); document.write( "y=4 [Also, checks out]
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\n" ); document.write( "So (x=3) and (y=4)
\n" ); document.write( "3(3)+(4)=13
\n" ); document.write( "9+4=13
\n" ); document.write( "13=13 [checks out}
\n" ); document.write( "and
\n" ); document.write( "3(3)+2(4)=17
\n" ); document.write( "9+8=17
\n" ); document.write( "17=17 [Also checks out]\r
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