Répondre :
(6x+15)(x-1)+(9-12x)(x-3)+(20x-15)=0
3(2x+5)(x-1)+3(3-4x)(x-3)+5(4x-3)=0
3(2x+5)(x-1)+(3-4x)(3x-9-5)=0
3(2x+5)(x-1)+(3-4x)(3x-14)=0
-6x²+74x-57=0
x=1/6(37-rac(1027) ou x=1/6(37+rac(1027)
3(2x+5)(x-1)+3(3-4x)(x-3)+5(4x-3)=0
3(2x+5)(x-1)+(3-4x)(3x-9-5)=0
3(2x+5)(x-1)+(3-4x)(3x-14)=0
-6x²+74x-57=0
x=1/6(37-rac(1027) ou x=1/6(37+rac(1027)