<h2>
Answer:</h2>
The expression which represents the perimeter P of the rectangle as a function of L is:

<h2>
Step-by-step explanation:</h2>
The length and width of a rectangle are denoted by L and W respectively.
Also the diagonal of a rectangle is: 10 inches.
We know that the diagonal of a rectangle in terms of L and W are given by:

( Since, the diagonal of a rectangle act as a hypotenuse of the right angled triangle and we use the Pythagorean Theorem )
Hence, we have:

But we know that width can't be negative. It has to be greater than 0.
Hence, we have:

Now, we know that the Perimeter of a rectangle is given by:

Here we have:

Answer:
It is B
Step-by-step explanation:
Answer:
w=7
Step-by-step explanation:
3w+4w=49
7w=49
w=49/7
w=7