Well, since each doll hair is 22cm, and she had a total of 165cm.
Then number of dolls would be = 165/22 = 7.5
The actual number of dolls = 7. We would drop the .5.
7, Seven.
Given:
The equation is

To find:
The properties which is not used from the given options.
Solution:
We have,

Using Multiplication Property of Equality, multiply both sides by 2.

(Distributive Property)
Using Subtraction Property of Equality, subtract 6n from both sides.
From the given options only one property is not used, i.e., Zero Product Property.
Therefore, the correct option is D.
23 x 8 is equal to 184. 23+23+23+23+23+23+23+23. 184 ÷ 8 = 123
6 minutes and a few seconds