translate the statement into an equation: the difference of four times a number and eight is equal to twenty-three less than that number

Let, the number be "x"
Now,
according to the question,
4x -8 = x -23This is your equation.

Now solving it,
4x - 8 = x - 23
4x - x = -23 + 8
3x = -15
x = -15 / 3
x = -5

Checking the answer,
4 (-5) - 8 = (-5) - 23
-20 - 8 = -5 - 23
-28 = -28true

X - a number