Answer:
5z - 9
Explanation:
Distributive property mean you will multiply everything in parentheses by what is on the outside of the parentheses. 1/2 x 12 and 1/2 x 10z
1/2(12 + 10z) - 15
6 + 5z - 15
Now combine like terms. There are only two like terms 6 and -15. 5z is not a like term because it has the variable.
5z - 9