Answer:
The width of the room is 
Step-by-step explanation:
we know that
The area of rectangle (area of the room) is equal to

we have


substitute the values in the formula and solve for W



Answer:
The answer is option (C)=an-1+7
Step-by-step explanation:
A recursive rule is a formula that in which each term is expressed as a function of its preceding term(s), meaning in order to get to the nth term you have to express it in a form of the term that comes before it. In our case the a(n-1) term
So for the sequence -9, -2, 5, 12
The nth term is any number on the sequence and
- -2 is the a(n-1) term for -9
- 5 is the a(n-1) term for -2
- 12 is the a(n-1) term for 5
So we need to find out what we have to do to the preceding term to get the next.
To get -2 from -9 we have to add 7 to -9; -9+7=-2
To get 5 from -2 we have to add 7 to -2; -2+7=5
To get 12 from 5 we add 7 to 5; 7+5=12
So the recursive rule would be= a n-1+7
I think that the answer is C. 10