Verified Answer :

3 + 9(8k + 9)
98k = 72k
9
9=81
3+ 72k + 81
72k + 84

Answer: 72k + 84

Here is what you do.... PEMDAS! Parenthesis,Exponents,Multiplication,Division,Add,Subtract. So you would do 8k+9 which would be 17k and now the problem is 1217k.... which would be 209k. But if they ask for the equation then it would be 1217k. :)