Add 30 to both sides: 3x^2+33x+30=0
Divide both sides by 3: x^2+11x+10=0
Factor / Complete the square: (x+10)(x+1)=0
Zero Product Property Rule: x+10=0 and x+1=0, x=-10 and x=-1
So the zeroes of the quadratic are -10 and -1
Hope this helped!
