Whats the smallest zero for the function y = 4x^2-8x 60

The smallest zero for your equation is either -3 or 2.
Since you didn't gave us what 60 was either positive or negative, I had to write it in both forms.
Which are y=4x^2-8x+60 or y=4x^2-8x-60.
If your equation has it with a positive 60 then the smallest zero is 2.
If your equation has it with a negative 60 then the smallest zero is -3.
If you need any further explanation due to how I got the answer just let me know. (: