Set equal to eachother
(2x+1) = 79
Subtract 1 from both sides
2x=78
Divide 2 from both sides
2x/2=78/2
X= 39
Let the number be 'x'
Since, the product of number and 4 less than twice that number is 336.
![x \times [(2 \times x) -4] = 336](https://tex.z-dn.net/?f=x%20%5Ctimes%20%5B%282%20%5Ctimes%20x%29%20-4%5D%20%3D%20336)
![x[2x -4] = 336](https://tex.z-dn.net/?f=x%5B2x%20-4%5D%20%3D%20336)


Now, we will split the middle term, we get



So, 
So, x = 14 or x = -12
Therefore, the negative number is '-12'.