P=4*a, where P - perimeter, a - length of one side of the square.
if a=x+3 and P=48, then 4(x+3)=48;
x=9.
Answer: 9 units.
The answer is D, i.e. the system was solved via elimination
If you multiply the first equation by 5, the system becomes

If you sum the two equations, you get

And so if you substitute the second equation of system A with this new equation, you'll get system B.
Answer:
50 meters per day
Step-by-step explanation:
Answer:
A. Gasoline
Step-by-step explanation: