Finding x and y intercepts

I know what the x and y intercepts but how do i show that mathematically for:

1. y= x^3-12x+8
The y-int= 0,8
x=3 and 2/3.. i think

2. y=(1/3x )(4-x)^2
y-int= 0
x-int= 0,4

any help would be appreciated. Thanks

To find x-intercept(s), set y equal to zero, and solve.

To find y-intercept(s), set x equal to zero, and solve.

Eliz.