Question 1158897
Who is Helen?  She was not part of the description.


y, John
x, Lyn
{{{system(y-21=3(x-21),y=2x)}}}

-

{{{2x-21=3(x-21)}}}

{{{2x-21=3x-63}}}

{{{63-21=x}}}

{{{x=42}}}-------------Lyn, now
-
{{{y=84}}}-----------John now



You can just subtract 21 from each to see age of each when they were married twentyone years ago.