Question 716459
Subtraction method?
Multiply both sides of (2) by {{{ 2 }}}
and subtract (2) from (1)
{{{ 6x +14y =54
{{{ -6x - 10y =-60 }}}
{{{ 4y = -6 }}}
{{{ y = -3/2 }}}
Substitute this result back into (1) or (2)
{{{ 3x+5y=30 }}}
{{{ 3x+5*(-3/2) = 30 }}}
{{{ 3x = 30 + 15/2 }}}
{{{ 3x = 75/2 }}}
{{{ x = 25/2 }}}
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check the answers:
{{{ 6x+14y = 54 }}}
{{{ 3x + 7y = 27 }}}
{{{ 3*(25/2) + 7*(-3/2) = 27 }}}
{{{ 75 - 21 = 54 }}}
{{{ 54 = 54 }}}
OK
You can check the other equation