Réponses

2012-12-04T21:22:48+01:00

(2x-9)(8x-1)= 16x²-2x-72x+1 = 16x²-74x+1

16x²-74x+1 = (4x-5)² (identité remarquable)

16x²-74x+1 = (16x²-40x+25)

16x²-74x-16x²+40x =25-1

-34x = 24 donc x = 24/-34 = 12/-17