Question 70245
Let L=larger number and S=smaller. The larger number (L) can be represented as 12 more than the smaller (or equal to 12+smaller). So
{{{L=12+S}}} 
And we're given the fact that the sum of the smaller and twice the larger is 39 which can be represented as
{{{S+2L=39}}}
Now the L from the first equation can be substituted into the 2nd equation
{{{S+2*highlight(12+S)=39}}}Now solve for S
{{{S+24+2S=39}}}
{{{3S+24=39}}}
{{{3S=15}}}
{{{S=5}}}
Now plug this back into the first equation
{{{L=12+highlight(5)}}}
{{{L=17}}}
So the smaller number is 5 and the larger is 17.