Разложите на множители:

а) x (x-4) - 5 (4-x)

b) b (b-1) + (1-b)

v) 2 (p-2) + p (2-p)

а) x (x-4) - 5 (4-x) = x (x-4) + 5 (x-4) = (x-4) (x+5)

b) b (b-1) + (1-b) = b (b-1) - (b-1) = (b-1) (b-1) = (b-1) ^2

v) 2 (p-2) + p (2-p) = - 2 (2-p) + p (2-p) = (2-p) (p-2) = - (2-p) (2+p) = - (4-p^2) = p^2-4

a) x^2 - 4x - 20 + 5x = 0

x^2 + x - 20 = 0

D = 1 + 80 = 81 = 9^2

x1 = (-1 - 9) / 2

x1 = - 5

x2 = (-1+9) / 2

x2 = 4

2) b^2 - b + 1 - b = 0

b^2 - 2b + 1 = 0

d = 4 - 4 = 0

d1 = 2/2 = 1

3) 2p - 4 + 2p - p^2

-p^2 + 4p - 4=0

p^2 - 4p + 4=0

D = 16 - 16 = 0

P1 = 4/2 = 2