Area of a square = Side × Side
Side = 7x-3
Area of the square = (7x-3) × (7x-3)
= 7x(7x-3) -3(7x-3)
= 49x^2 -21x -21x +9
=49x^2 -42x +9
Answer:

<em>Sure hope this helps you :D</em>
Answer: Boat cost $ 3200
Trailer cost $ 800
Step-by-step explanation: From the statement , the coat of Trailer (t) = 1/4 of the coat of the boat ( b)
i.e t = 1/4b
multiply through by 4
4t = b
both cost 4,000
i.e t + b = 4000
recall: b = 4t
therefore
t + 4t = 4000
5t = 4000
t = 4000/5
t = 800
b = 4000 - 800
b = 3200
Y = 7.50x.....y = earnings per week , x = number of packages delivered
48 packages.....so x = 48
y = 7.50(48)
y = 360.....so if he delivers 48 packages, he earns $ 360