Question 61709
What they are asking is to find three 
different points on the line {{{y = 3x}}}
The points are in the form (x,y)
One at a time
(0,_)
{{{y = 3*0}}}
{{{y = 0}}}
(0, 0) answer
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(-1,_)
{{{y = 3*(-1)}}}
{{{y = -3}}}
(-1, -3) answer
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(7,_)
{{{y = 3*7}}}
{{{y = 21}}}
(7, 21) answer