Question 159943
Convert to slope-intercept form, {{{y=mx+b}}}
{{{x+3y=6}}}
{{{3y=-x+6}}}
{{{y=-(1/3)x+2}}}
Plot the y-intercept (0,2).
{{{drawing( 300, 300, -5, 5, -5, 5,grid( 1 ),circle( 0, 2, .2 ))}}}
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The slope is (-1/3) so for slope down as you move to the right. 3 unit steps change in x, give one negative unit step change in y. 
So (0,2)+(3,-1)=(3,1) 
Plot that point.
{{{drawing( 300, 300, -5, 5, -5, 5,grid( 1 ),circle(3,1,.2),circle( 0, 2, .2 ))}}}
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Connect the points with your line.
{{{drawing( 300, 300, -5, 5, -5, 5,grid( 1 ),green(line(-12,6,12,-2)),circle(3,1,.2),circle( 0, 2, .2 ))}}}