exeecice 80 svp merci davance

bonjour,

A = a²-b² = (7x-4)(7x=4)

B = a²-2ab+b² =(3y-4)²

C = a²+2ab+b² = (x+1)²

D =  a²-b² = (5-10t)(5+10t)

E = ..........= (6z-1)(6z+1)

F  = a²-2ab+b² = (8-5x)²

Exercice 80 : 

Il existe 3 identités remarquables à connaître : 
(a + b)² = a² + 2 * a * b + b²
(a - b)² = a² - 2 * a * b + b²
(a + b) (a - b) = a² - b²

A = 49x² - 16
A = (7x)² - 4²
A = (7x - 4) (7x + 4)

B = 9y² - 24y + 16
B = (3y)² - 2 * 12 * y + 4²
B = (3y - 4)²

C = x² + 2x + 1
C = x² + 2 * x * 1 + 1²
C = (x + 1)²

D = 25 - 100t²
D = 5² - 10t²
D = (5 - 10t) (5 + 10t)

E = 36z² - 1
E = (6z)² - 1²
E = (6z - 1) (6z + 1)

F = 64 - 80x + 25x²
F = 8² - 2 * 40 * x + (5x)²
F = (8 - 5x)²