# Can you solve a math problem: x+y=42, x-y=30?

In page 43, math problem 1, on Math 4 Workbook, Part One, Vietnamese Education Publishing House:

*The sum of mother and son's ages is 42. The mother is 30 years older than her son. How old is the mother and her son?*

Try something like:

(Or just ignore sage code, and use plain thoughts or simple drawings.)