Let the number be 'x'
Since, the product of number and 4 less than twice that number is 336.
[tex]x \times [(2 \times x) -4] = 336[/tex]
[tex]x[2x -4] = 336[/tex]
[tex]2x^2 -4x- 336=0[/tex]
[tex]x^2-2x-168=0[/tex]
Now, we will split the middle term, we get
[tex]x^2-14x+12x-168=0[/tex]
[tex]x(x-14)+12(x-14)=0[/tex]
[tex](x-14)(x+12)=0[/tex]
So, [tex](x-14)=0 or (x+12)=0[/tex]
So, x = 14 or x = -12
Therefore, the negative number is '-12'.
