Question 58667
{{{ 8x -4y = 16 }}}
{{{ y = 2x -4 }}}
Substitute the second equation into the first
{{{ 8x -4(2x - 4) = 16 }}}
Distribute the -4
{{{ 8x - 8x + 16 = 16 }}}
combine like terms
{{{ 16 = 16 }}}
Because the X values canceled and you are left with a number equalling itself .... ANY oredered pair will satisfy the equations, because they are the EXACT same line