Question

Becky wants to fence in a rectangular play area for her dog. If she was 82 feet of fencing and wants the length of the play area to be 9 feet longer than its width then what should the dimensions of the play area be?

Answer 1

length= width+9    ----- Now we can substitute length with width!
Perimeter = 2(length) + 2(width)
Perimeter = 82
82= 2(w+9) + 2w
41 = w+ 9 + w
41-9 = 2w
32 = 2w
16= w    (now plug w into the equation for length)
length = 16 + 9 = 25

SOO... Dimensions = 16 x 25

Answer 2

ok
fencing=perimiter
perimiter=L+L+W+W=2L+2W=2(L+W)
82=2(L+W)
divid eboth sides by 2 for ease of use
41=L+W


if she wants legnth to be 9 more than width, then
L=9+W
subsitute 9+W for L
41=9+W+W
41=9+2W
subtract 9
32=2W
divide 2
16=W

subsitute
L=9+W
L=9+16
L=25



the pen should be 25 feet by 16 feet