Answer:
27k^2+51k+20
Step-by-step explanation:
Distribute the 3k to both 9k and 5. Then distribute 4 to the 9k and the 5. When you multiply the 3k and 9k it gives you the 27^2. 3k times 5 gives you 15k. 4 times 9k is 35k. 4 times 5 is 20. Combine like terms. 15k plus 35k is 51k. When put in order you get the above answer!