Question

Mary is x years old. How old will she be in 10 years? How old was she 2 years ago?

Answer 1

We know that Mary is x years old.

The age in 10 years will be x plus 10, as follows:

`M_{\text{age}+10}=x+10`

And the age she had two years ago was:

`M_{\text{age}-2}=x-2`

An example of this could be: imagine that Mary is 10 years now. In ten years, she will have:

10 + 10 = 20 years ( we add 10 to the original number). Likewise, 2 years ago, she had 10-2 = 8 years.

Therefore, the answers are two equations:

`M_(age+10)=x+10`
`M_{\text{age}-2}=x-2`