Answer:
Step-by-step explanation:
First, we can divide out the common factor, 6
[tex]6x^2 + 120x + 2070 = 0\\x^2 + 20x + 345 = 0\\[/tex]
Now we complete the square
[tex](x^2 + 20x + (\frac{20}{2})^2) + 345 - (\frac{20}{2})^2\\(x^2 + 20x + 100) + 345 - 100\\(x+10)^2 + 245\\[/tex]
[tex](x+10)^2 = -245\\x + 10 = \sqrt{-245}\\x = i\sqrt{245} - 10\\x = -10 \pm i\sqrt{245}[/tex]
