(b - 3)*(b - 4) - (b + 4)*2
(b - 3)*(b - 4) - (b + 4)*2 при b = 4
((4) - 3)*((4) - 4) - ((4) + 4)*2
(4 - 3)*(4 - 4) - (4 + 4)*2
-16
-8 - 2*b + (-4 + b)*(-3 + b)
-8.0 - 2.0*b + (-4.0 + b)*(-3.0 + b)
2 4 + b - 9*b