Pour les exercices 51 a 53 factoriser chaque expression merci d avance

bonjour
A = a²+ 3 a
A = a ( a + 3)
B = 4 b² - 12
B = 4 ( b² - 3 )
A = 2 t² - 3 t
A = t ( 2 t - 3 )
B = 4 x² + 20 x
B = 4 x ( x + 5 )
A = - 5 x² + 25 x
A = 5 x ( - x + 5 )
B = - 10 - 16 a
B = 2 ( - 5 - 8 a)