Question 1002920
{{{ x + 3y = -7 }}}
Multiply both sides by {{{ 3 }}} and subtract
this equation from the other one
{{{ 3x - 2y = 12 }}}
{{{ -3x -9y = 21 }}}
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{{{ -11y = 33 }}}
Divide both sides by {{{ -11 }}}
{{{ y = -3 }}}
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Plug this result back into one of the equations
{{{ x + 3*(-3) = -7 }}}
{{{ x - 9 = -7 }}}
Add {{{ 9 }}} to both sides
{{{ x = 2 }}}
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{{{ x = 2 }}}
{{{ y = -3 }}}