The answer is 12 inches for one side of the cover
<span> 2(2x-3y=3)..................4x-6y=6..........equation 1
3(5x+2y=17)
...........15x+6y=51</span>........equation 2
adding equation 1 and equation 2;
19x=57
x=3
2x-3y=3
(2*3)-3y=3
6-3=3y
y=1
Add 1 to both sides:

In cases like this, we have to remember that a root is always positive, so we can square both sides only assuming that

Under this assumption, we square both sides and we have

The solutions to this equation are

But since we can only accept solutions greater than -1, we discard
and accept
.
In fact, we have

and

which is the only solution.
The length of the rectangle is 10, while the width of the rectangle is 5.
Answer: 12 hours
Step-by-step explanation:
Let x = time it takes to fill the pool if the inlet pipe and drain pipe are both open
1/6 = portion of pool filled per hour by the inlet pipe
1/12 = portion of pool emptied per hour by the drain
1/x = portion of pool filled per hour if the inlet pipe and drain are both open
Then, 1/6 - 1/12 = 1/x
Multiply by the LCD, 12x, to obtain
2x - x = 12
x = 12 hours