Question

Tìm x biết 5x.(2-3.x)=4-6x

Answer 1

5x(2-3x)=4-6x

<=>10x-15x²=4-6x

<=>10x+6x-4-15x²=0

<=>-15x²+16x-4=0

<=>-15(x²-16/15.x+4/15)=0

<=>x²-2/5.x-2/3.x+4/15=0

<=>x(x-2/5)-2/3.(x-2/5)=0

<=>(x-2/3)(x-2/5)=0

<=> x-2/3=0 hoặc x-2/5=0

<=>x=2/3 hoặc x=2/5

Answer 2

5x.(2-3.x)=4-6x

5x(2-3x)=2(2-3x)

5x(2-3x)-2(2-3x)=0

(2-3x)(5x-2)=0

=>2-3x=0 hoặc 5x-2=0

     -3x =-2 hoặc 5x=2

       x =2/3 hoặc x=2/5

Vậy x=2/3;2/5