Need help, please explain the answer

7 - x meters

Step-by-step explanation:

This is a difference of squares. The formula for difference of squares is

a^2-b^2 = (a-b)(a+b)

So plug the numbers we know into this formula.

Area = lw

49 - x^2 = (a-b)(7+x)

49 - x^2 = (7-x)(7+x)

The length is 7 - x meters.

practice. practice. practice.

twenty-six miles over two gallons because the proportion for the original 13 miles to one gallon would be written 13/1 and, doing the same thing to the top and bottom, i multiplied by 2 and got 26/2