Question 196978
You have the basic equations correct
{{{(x+y)/2 = 7 }}}
{{{x+y = 14}}}

{{{3x = y/2}}}
{{{6x = y}}}

So
{{{x+y = 14}}}
{{{x + 6x = 14}}}}
{{{7x = 14}}}
{{{x = 2}}}

And {{{6*2 = y}}}
{{{12 = y}}}

Check for answers. Is the average of 2 and 12 = 7?