9. The perimeter of a rectangular wooden deck is 90 feet. The deck's length, 1 , is 5 feet less than 4 times its width, w. Which system of linear equations can be used to determine the dimensions, in feet, of the wooden deck?

To find the dimensions of the rectangular wooden deck, you can set up two equations based on the given information. The perimeter P of a rectangle is calculated as \(P = 2l + 2w\), where l is the length and w is the width. Given the perimeter is 90 feet, the first equation will be \(2l + 2w = 90\). For the second equation, since the length l is stated to be 5 feet less than 4 times the width, we can write this as \(l = 4w - 5\). Therefore, the system of linear equations is \(2l + 2w = 90\) and \(l = 4w - 5\). Now you’re all set to solve and find those dimensions! And here’s a little hint: when solving systems of linear equations, substitution or elimination methods can both be your best friends. Make sure to keep a keen eye on your calculations, as it’s easy to slip up with signs or operations. Good luck!