Question 120115
{{{x + 2y = 4}}}
(0,2) yes
{{{0 + 2*2 = 4}}}
{{{4 = 4}}}
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(4,0) yes
{{{4 + 2*0 = 4}}}
{{{4 = 4}}}
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(0,-2) no
{{{0 + 2*(-2) = 4}}}
{{{-4 = 4}}} not true
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(-8,6) yes
{{{-8 + 2*6 = 4}}}
{{{-8 + 12 = 4}}}
{{{4 = 4}}}