Question

(2x-3)2+(x-5)(x+5)-(x+4) 2

Answer 1

Vejamos: (2x - 3)^2 + (x - 5).(x + 5) - (x + 4)^2 = 4x^2 - 12x + 9 + x^2 - 25 - x^2 + 8x + 16 = 4x^2 + x^2 - x^2 - 12x + 8x + 9 - 25 + 16 = 4x^2 - 4x