The zero of a polynomial is the value which, when placed as the variable in the equation, makes the equation equal to zero. In this case, we have the equation
p(x) = x - 4
So the zero would be the value that, when put in the place of x, makes it equal to zero. Since all that's being done on the equation is subtracting four, then all we need to do to make the equation equal to zero is to add that 4 back, since
4 - 4 = 0
And our equation would look like this:
p(x) = (4) - 4
The zero of the polynomial p(x) = x - 4 is where x = 4.
Hope that helped! =)
