Answer: The correct option is A.
Step-by-step explanation: We are given a polynomial which is a sum of other 2 polynomials.
We are given the resultant polynomial which is : 
One of the polynomial which are added up is : 
Let the other polynomial be 'x'
According to the question:


Solving the like terms in above equation we get:


Hence, the correct option is A.
Answer:
The dimensions of the yard are W=20ft and L=40ft.
Step-by-step explanation:
Let be:
W: width of the yard.
L:length.
Now, we can write the equation of that relates length and width:
(Equation #1)
The area of the yard can be expressed as (using equation #1 into #2):
(Equation #2)
Since the Area of the yard is
, then equation #2 turns into:

Now, we rearrange this equation:

We can divide the equation by 5 :

We need to find the solution for this quadratic. Let's find the factors of 160 that multiplied yields -160 and added yields -12. Let's choose -20 and 8, since
and
. The equation factorised looks like this:

Therefore the possible solutions are W=20 and W=-8. We discard W=-8 since width must be a positive number. To find the length, we substitute the value of W in equation #1:

Therefore, the dimensions of the yard are W=20ft and L=40ft.
First one is 7.73 (23.19/3)
Second one is 14.04 ((19.71/7.3) x 5.2)