document.write( "Question 281605: Point of intersection of the lines whose equations are y=-1/2x+3 and y=2x+8 \n" ); document.write( "

Algebra.Com's Answer #204581 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
I would get these both into the standard form
\n" ); document.write( "and solve simultaneously
\n" ); document.write( " $\"y+=+%28-1%2F2%29x+%2B+3\"$
\n" ); document.write( " $\"%281%2F2%29%2Ax+%2B+y+=+3\"$
\n" ); document.write( "(1) $\"x+%2B+2y+=+6\"$
\n" ); document.write( "and
\n" ); document.write( " $\"y+=+2x+%2B+8\"$
\n" ); document.write( "(2) $\"2x+-+y+=+-8\"$
\n" ); document.write( "Multiply both sides of (2) by $\"2\"$
\n" ); document.write( "and add (1) and (2)
\n" ); document.write( "(1) $\"x+%2B+2y+=+6\"$
\n" ); document.write( "(2) $\"4x+-+2y+=+-16\"$
\n" ); document.write( " $\"5x+=+-10\"$
\n" ); document.write( " $\"x+=+-2\"$
\n" ); document.write( "and, substituting,
\n" ); document.write( "(1) $\"-2+%2B+2y+=+6\"$
\n" ); document.write( " $\"2y+=+8\"$
\n" ); document.write( " $\"y+=+4\"$
\n" ); document.write( "The lines intersect at (-2,4)
\n" ); document.write( "here's the plot:
\n" ); document.write( " $\"+graph%28+500%2C+500%2C+-6%2C+8%2C+-6%2C+8%2C+%28-1%2F2%29%2Ax+%2B+3%2C+2x+%2B+8%29+\"$ \n" ); document.write( "

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