Answer:
;
and 
Step-by-step explanation:
Required
Select which expression equals 18

This gives:


This gives:


This gives:


This gives:


This gives:

From the above computations:
;
and
are equivalents of 18
Answer:
Option D
Step-by-step explanation:
Combine Like Terms.

Hope this helps.
Answer: 
Step-by-step explanation:

Add
on both sides and subtract
on both sides to leave x's on the left side and independent values on the right.


Solve the fractions.





Convert the mixed fraction
to an improper fraction. You can do this by multiplying 1 times 35 and adding 2.

Now use the reciprocal (inverse fraction) and multiply on both sides to isolate x.




The answer is choice A.
We're told that the left and right walls of the cube (LMN and PQR) are parallel planes. Any line contained in one of those planes will not meet another line contained in another plane. With choice A, it's possible to have the front and back walls be non-parallel and still meet the initial conditions. If this is the case, then OS won't be paralle to NR. Similarly, LP won't be parallel to MQ.