this is the answer
[tex]2x + y = 10 \\ y = - 2x + 10[/tex]
if substitute 1 and 2 and 3 as x then the points will be :
[tex] \binom{x}{y} \: \: \: \: \: \: \binom{1}{8} \: \: \: \: \: \: \binom{2}{6} \: \: \: \: \: \: \binom{3}{4} [/tex]
and that's the picture
good luck