Bonjour,
Factoriser :
= (5x+5)(8x-2)+25x²+50x+25
= 5(13x²+16x+3)
= 5(13x²+13x+3x+3)
= 5(13x(x+1)+3(x+1))
= 5(13x+3)(x+1)
Bonne journée.