Answer:
[tex]\huge\boxed{A=(9x^2-48x+64)ft^2}[/tex]
Step-by-step explanation:
The formula of an area of a square:
[tex]A=s^2[/tex]
[tex]s[/tex] - side of a square
We have [tex]s=(3x-8)ft[/tex]
Substitute:
[tex]A=(3x-8)^2[/tex]
METHOD 1:
Use [tex](a-b)^2=a^2-2ab+b^2[/tex]
[tex]A=(3x)^2-2(3x)(8)+8^2=9x^2-48x+64[/tex]
METHOD 2:
Use FOIL: [tex](a+b)(c+d)=ac+ad+bc+bd[/tex]
[tex]A=(3x-8)(3x-8)=(3x)(3x)+(3x)(-8)+(-8)(3x)+(-8)(-8)\\\\=9x^2-24x-24x+64=9x^2-48x+64[/tex]
