Given :

x-intercept is the value of x when f(x) = 0
so, f(x) = 0

x-intercept = 4
Root = x-intercept = 4
solution of the function = Root = x-intercept = 4
y-intercept is the value of f(x) when x = 0
so, x = 0

y-intercept = -8
The graph of the function will be as shown in the following image: