Answer:
1. Set A
2. [tex]\textsf{Apply\:Difference\:of\:Two\:Squares\:Formula:\:}\left(a+b\right)\left(a-b\right)=a^2-b^2[/tex]
3.
[tex](x+7)(x-7)[/tex]
[tex]\implies a=x\:\textsf{and}\:b=7[/tex]
[tex]\implies x^2-7^2=x^2-49[/tex]
[tex](x-9)(x+9)=(x+9)(x-9)[/tex]
[tex]\implies a=x\:\textsf{and}\:b=9[/tex]
[tex]\implies x^2-9^2=x^2-81[/tex]
[tex](4x-3)(4x+3)=(4x+3)(4x-3)[/tex]
[tex]\implies a=4x\:\textsf{and}\:b=3[/tex]
[tex]\implies (4x)^2-3^2=16x^2-9[/tex]
4.
[tex](2x+5)(2x-5)[/tex]
[tex]\implies a=2x\:\textsf{and}\:b=5[/tex]
[tex]\implies (2x)^2-5^2=4x^2-25[/tex]
5. [tex](x-6)(x-6)[/tex]
Cannot use Difference of Two Squares Formula to expand this expression. To expand this expression, you would need to use the FOIL method: [tex]\left(a+b\right)\left(c+d\right)=ac+ad+bc+bd[/tex]
[tex]\implies (x-6)(x-6)=x^2-6x-6x+(-6)^2=x^2-12x+36[/tex]
