product means multiplication
is means equal
less than means subtraction
times means multiplication
The product of 9 and a number is 12 less than three times that number.
Lets say this number is 'n'
then:
9n = 3n-12
Add 12 on both sides
9n + 12 = 3n
Subtract 9n on both sides
12 = -6n
Divide by -6 on both sides to isolate n
n= -2
Your final answer is
[tex]\Huge{\boxed{\bf{n=-2}}}[/tex]