Question 103661
{{{10x + 2y = 7}}}
But if you substitute {{{y = -5x + 3}}},

{{{10x+2(-5x+3)=7}}}
{{{10x+(-10x+6)=7}}}
{{{(10x-10x)+6=7}}}
{{{0+6=7}}}
{{{6=7}}}  ????


The equation lead into a false statement.

therefore, there is no solution


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