document.write( "Question 700783: How do I find y for this equation? 2x-y=1 I don't understand how to solve it and then graph it along with y=-3. \n" ); document.write( "
Algebra.Com's Answer #432006 by KMST(5328)\"\" \"About 
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ONE WAY TO FIND \"y\":
\n" ); document.write( "\"2x-y=1\" --> \"2x-y-1=1-1\" --> \"2x-y-1=0\" --> \"2x-y-1%2By=0%2By\" --> \"2x-1=y\" --> \"highlight%28y=2x-1%29\"
\n" ); document.write( "ANOTHER WAY:
\n" ); document.write( "\"2x-y=1\" --> \"2x-y-2x=1-2x\" --> \"-y=1-2x\" --> \"%28-1%29%28-y%29=%28-1%29%281-2x%29\" --> \"y=-1%2B2x\" --> \"highlight%28y=2x-1%29\"
\n" ); document.write( "Using \"y=2x-1\" you can calculate the coordinates of two points on the line,
\n" ); document.write( "and then you would just plot the points and connect them with a straight line.
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\n" ); document.write( "However, you can graph \"2x-y=1\" without transforming the equation into \"y=2x-1\".
\n" ); document.write( "To get the coordinates of a point on the line,
\n" ); document.write( "you can give a value to \"x\" (or to \"y\"),
\n" ); document.write( "and solve for the other variable.
\n" ); document.write( "For \"x=0\", substituting into \"2x-y=1\" we get
\n" ); document.write( "\"2%2A0-y=1\" --> \"0-y=1\" --> \"-y=1\" --> \"y=-1\".
\n" ); document.write( "That gives us the point (0,-1), with \"x=0\" and \"y=-1\".
\n" ); document.write( "For \"x=3\", we get
\n" ); document.write( "\"2%2A3-y=1\" --> \"6-y=1\" --> \"-y=1-6\" --> \"-y=-5\" --> \"y=5\"
\n" ); document.write( "That gives us the point (3,5).
\n" ); document.write( "Plotting (0,-1) and (3, 5} we get
\n" ); document.write( "Adding the line, we get
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\n" ); document.write( "On the line for \"y=-3\", all the points have \"y=-3\", for any and all values of \"x\".
\n" ); document.write( "Adding that line (in green), we get:
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