Answer
Required numbers are $18$ and $6$.
Work Step by Step
Let''s assume that one number is '$x$' and another is '$y$' and also $x\gt y$.
Therefore according to first condition-
$x+y$ = $2(x-y)$
i.e. $x+y$ = $2x-2y$
i.e. $x-3y$ = $0$ __eq.1
And, according to second condition-
$x$ = $2y+6$ __eq.2
Substituting for '$x$' in eq.1-
$x-3y$ = $0$
i.e. $2y+6-3y$ = $0$
i.e. $-y$ = $-6$
i.e. $y$ = $6$
Substituting for '$y$' in eq.2-
$x$ = $2(6)+6$ = $18$
Therefore the two numbers are $18$ and $6$.
