Answer:
Let the unknown number be x ;

Step-by-step explanation:
I think the answer is 18.
Equation/ steps:
12+v=30
30-12= 18
V=18
Hope this helps!
Answer:
B because it represents the lowest value
Step-by-step explanation:
The length of rectangular swimming pool = 25 feet
The width of the swimming pool = 12 feet
The pool is surrounded by a fence which is h feet from each side
So, length of fence becomes = 25+2h
Width of fence becomes = 12+2h
The expression for the length of the fence is 25+2h feet
2h because 'h' increases for both ends of the length of the pool.