Question 110548
{{{x + y = 12}}}

But, {{{y=2x}}}. So,


{{{x+(2x)=12}}}
{{{x+2x=12}}}
{{{3x=12}}}
{{{3x/3=12/3}}}
{{{x(3/3)=4}}}
{{{x*1=4}}}
{{{x=4}}}


Again, {{{y=2x}}} So,

{{{y=2*4=8}}}


Thus, x=4 and y=8.


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