Dear student,
Let the present age of Sahil be x , so Sahil's mother age is 3x.
After, 5 years, Sahil age x+5 and Sahil's mother age be 3x+5
According to the question,
x+5+3x+5=66
4x+10=66
4x=56
x=14 years
So, Sahil age is 14 yrs, and his mother age is 42(3×14).
Regards