Albert is A years old. Mom is M years old.
Six years ago: A = M/5
Now: 3*(A+6) = M+6
Substitute M/5 for A in the second equation.
3*(M/5 + 6) = M+6
3M/5 + 18 = M+6
12 = M - 3M/5 = 5M/5 - 3M/5 = 2M/5
60 = 2M
30 = M
The question asks how old is Albert's mom. Remember, we called M her age 6 years ago. So now her age is 30+6 = 36.