Question 881627
{{{drawing(300,300,-10,10,-10,10,grid(1),
circle(1,3,0.2),
circle(2,0,0.2),
circle(3,-3,0.2),
circle(4,-6,0.2))}}}
Looks like a straight line. 
Calculate the slope (change in y divided by change in x) for any two points.
{{{m=(0-3)/(2-1)=-3}}}
{{{y=-3x+b}}}
Use any point to solve for {{{b}}}
{{{3=-3(1)+b}}}
{{{b=6}}}
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{{{highlight(y=-3x+6)}}}
{{{drawing(300,300,-10,10,-10,10,grid(1),
circle(1,3,0.2),
circle(2,0,0.2),
circle(3,-3,0.2),
circle(4,-6,0.2),graph(300,300,-10,10,-10,10,-3x+6))}}}