Question 1207628

{{{3x-y=-4}}}..........eq.1
{{{5x+9y}}}=-28.....eq.2
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{{{3x-y=-4}}}..........eq.1, solve for {{{y}}}
{{{3x+4=y}}}..........eq.1a....substitute in eq.2


{{{5x+9(3x+4)=-28}}}.....eq.2, solve for{{{ x}}}
{{{5x+27x+36=-28}}}
{{{32x=-28-36}}}
{{{32x=-64}}}
{{{x=-64/32}}}
{{{x=-2}}}

go to {{{3x+4=y}}}..........eq.1a, substitute {{{x}}}
{{{y=3(-2)+4}}}
{{{y=-6+4}}}
{{{y=-2}}}


Solution:
{{{x=-2}}}
{{{y=-2}}}