1. Move 3x to the other side and subtract it from -9x 2. Factor out 3x 3. Divide both sides by 3 4. Since there are only factors left and they equal 0, one answer must be 0. 5. Solve the equation for x (where you will get the other 2 answers).
You can type that equation into Photomath and it will show you how to find the zeros.