(x-7)^2=?
(2x^2+5)^2=?
(8x^2+9)(8x^2-9)=?
(x^2-3y^3)^2=?
(x-6) (x+6)=?

(x-7)^2=x^2-28x+49

(2x^2+5)^2=4x^2+20x+25

(8x^2+9)(8x^2-9)=64x^4-81

(x^2-3y^3)^2=x^4-6x^2 y^3+9y^6

(x-6)(x+6)=x^2-36