(x+1)(x-1)-(x+5)(x-5)+(x+1)(x-5)

(x+1)(x-1)-(x+5)(x-5)+(x+1)(x-5) = x^2 - 1 - (x^2 - 25) + (x^2 - 5x + x - 5) = x^2 - 1 - x^2 + 25 + x^2 - 5x + x - 5 = -1 + 25 - 5 = 19