An official playing field (including end zone) for the indoor football league has a length 45 yd longer than its width. the perimeter of the rectangular field is 174 yd. find the length

So you know the perimeter form is = 2(l + w) or l + l + w + w

So the length is 45 + w following the formula

2(45 + w) + 2w = 174

90 + 2w + 2w = 174

4w = 84
w= 21

So the length is 45 + w, w= 21

45+ 21 = 66

Hope this helps!