$x=0$ should also be included.
Work Step by Step
Solving the problem correctly, we find: $$3x\left(x+4\right)\left(x-4\right)=0 \\ x=0,\:x=-4,\:x=4$$
You can help us out by revising, improving and updating this answer.Update this answer
After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.