(2x+3)²= (3+5x)²= (2x-5)²= (5-3x)²=

4x^2 + 12x + 9
= 9 + 30x + 25x^2
= 4x^2 -20x - 25
= 25 - 30x + 9x^2

(2x+3)(2x+3) = 4x²+6x+6x+9
                      =4x²+12a+9
(3+5x)(3+5x)= 9+15x+15x+25x² = 9+30x+25x²
(2x-5)(2x-5)= 4x²-10x-10x+25= 4x²-20x+25
(5-3x)(5-3x)= 25-15x-15x+9X²=25-30x+9x²