First we need to expand the first bracket by multiplying c by 5c^2 and 10 by 5c^2, so we get:
5c^3+ 50c^2
Then we need to expand the 2nd bracket.We do the same as before and multiply everything inside the bracket by -4c. We get
-8c^3+ 24c^2-4c
Put this two together and we have:
5c^3 + 50c^2 -8c^3+24c^2-4c
Now we collect like terms get:
-3c^3+74c^2-4c
I hope this help!
