Answer:
9. -35+7n
10. 16m+8
11. 6xy-6xz
Explanation:
You multiplying the terms inside the ( ) by the outside factor.
This is call distributive property, a(b+c)=ab+ac.
Also, a(b+c)=(b+c)a by commutative property.
It also works over the operation subtraction since subtraction is just a disguised addition (addition of the opposite). That is, a(b-c)=ab-ac.
Anyhow, let's look at 9.,10., and 11..
9.
-7(5-n)
(-7)(5-n)
(-7)(5)-(-7)(n)
-35+7n
10.
8(2m+1)
(8)(2m)+(8)(1)
16m+8
11.
6x(y-z)
(6x)(y-z)
(6x)(y)-(6x)(z)
6xy-6xz
Hint on 7. It's like all the other problems. That is, it is equivalent to doing 8(2+g).
If you want comment below, if you want me to check any of yours or if you have any questions.