IT WOULD BE "D" I BELIEVE
HOPE IM RIGHT AND THIS HELPS
Answer:
b and c
Step-by-step explanation:
For this case we have the following system of equations:

We can write a system of equivalent equations.
For this, it is enough to multiply one of the two equations by a scalar.
Multiplying the equation 1 by 2, we have:

Therefore, the new system of equations is:

Answer:
A system that is equivalent is:
D) 
Answer:
The length of the long side is 147 ft
The length of the short side is 30 ft
Step-by-step explanation:
L=5s-3
s= 324-2L
324=2(5s-3)+s
distribute
324=10s-6+s
simplify
324=11s-6
add 6 to both sides
330=11s
divide by 11
30=s
Plug in the s value to determine the length of the long side