If you would have to graph x=7, you probably know that this is a vertical line at, well, x=7.
| x | = 7 is nothing more than two vertical lines, namely x=7 or x=-7, as you already wrote down.
| x | = -8 has no (real) solutions, so there is nothing to graph.
Cuboid C is 4 and 4. Cuboid D is 2 and 4.
Answer:
C. 
Step-by-step explanation:
Given that A and B are matrices and
is a scalar, then the distributive property of scalar multiplication over addition is given by;

The distributive property of scalar multiplication over subtraction is

The correct answer is C.