A) 24
All side lengths of a square are equal so you take the square root of 576 to get two 24. If you try it back: 24*24 (w*h) to get 576.
The algebraic expressions can be written as

The given expression is,
X=amout the shirts cost
52=8+6.50+2x
add 8 and 6.5
52=14.5+2x
subtract 14.5 from 52
37.5=2x
divide 37.5 by 2
x=18.75
It cost $18.75 for each shirt.
-3/2x
The rational expression would not be defined only when the denominator is divided by 0
That is:
2x =0
x = 0/2
x =0
Hence it would not be defined when x = 0.
Hope this helps.