Question 920715

{{{ y-4x=8}}}
{{{y=2(2x+4) }}}
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{{{ y-4x=8}}}
{{{y=4x+8 }}}
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{{{-4x+y=8}}}
{{{-4x+y=8 }}}


*[invoke solve_by_graphing -4, 1, 8, -4, 1, 8]