Answer:
15a^5b^15
Step-by-step explanation:
you multiply 5 and 3 to get 15, and then when you are multiplying exponents of variables, you actually add them, so a^2 times a^3 is actually a^5, and b^7 times b^8 is b^15. Because these are all multiplied together, you get the answer of 15a^5b^15.
