To solve this question you have to use the quadratic equation. So since the problem is already in standard form it will be pretty easy. So the quadratic equation is x=-b±√b²-4ac/2a. Not sure if it makes sense through a computer xD Anywho, you just have to input the values in the equation into the quadratic equation. From your problem a=3 b=6 and c=15. So just substitute those into the quadratic equation then simplify. In the end you should get -6±12i/6. Divide everything by 6 and you should get -1<span>±2i!