Question 987529


{{{8x-6y=12}}}
{{{12x-ay=18 }}}
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{{{8x-12=6y}}}
{{{12x-18=ay}}}
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{{{8x/6-12/6=y}}}
{{{12x/a-18/a=y}}}
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{{{(4/3)x-2=y}}}
{{{(12/a)x-18/a=y}}}
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this will be equal {{{only}}} if:
{{{4/3=12/a}}}=>{{{a=9}}}
{{{18/a=2}}}=>{{{a=9}}}

so, your answer is: {{{a=9}}}