You can
put this solution on YOUR website!Let's make

for all reference.
1st condition:

, Sue's age

, leah being 6 years older than Sue
2nd condition:

, John being 5 years older than Leah
Equating to totasl age:

--------> working eqn

------------->

years old (Sue)
Leah=

, 6 years older than Sue
John=

, 5 years older than Leah
In doubt? go back to our condition & working eqn.

Thank you,
Jojo