Hello.
In 10 years, his age will be
[tex]\mathrm{z+10}[/tex]
The sum of his current age and 10 equals his age in 10 years.
2 years ago his age was
[tex]\mathrm{z-2}[/tex]
The difference of his current age and 2 equals his age 2 years ago.
7 years ago his age was
[tex]\mathrm{z-7}[/tex]
The difference of his current age and 7 equals his age 7 years ago.
Therefore, his age after 10 years will be [tex]\mathrm{z+10}[/tex], his age 2 years ago was [tex]\mathrm{z-2}[/tex], and his age 7 years ago was [tex]\mathrm{z-7}[/tex]
I hope it helps.
Have a nice day.
[tex]\boxed{imperturbability}[/tex]
