y = 3x - 4
Set y as 0 to find what x is when y is 0.
0 = 3x - 4
Add 4 to both sides.
4 = 3x
Divide both sides by 3.
1.3333 = x
x = 1.3333 when y = 0.
Check your work.
0 = (3)1.3333 - 4
0 = 4 - 4
0 = 0
This is correct.
So the answer is x is 1.3333, which is 4/3 (four thirds), when y is 0.