Question

I need help on #23! I do not get this at all. Someone please help me

Answer 1

Lenght is 4 + w
Width w

Answer 2

(w+4)(w) = 96
w² + 4w = 96
w² + 4w + 4 = 96 + 4
(w + 2)² = 100
w + 2 = 10 
w = 8
$l$ = 8 + 4
$l$ = 12

8ft x 12ft