Help! I'm working on this quadratic equation:

5x^2 = -30x - 65

I've got most of it understood, only I've reached a part in the equation where I need some help. Here:

30 +/- 2i sqrt(100) / 10

I'm not sure how to progress!

Question

Help! I'm working on this quadratic equation:

5x^2 = -30x - 65

I've got most of it understood, only I've reached a part in the equation where I need some help. Here:

30 +/- 2i sqrt(100) / 10

I'm not sure how to progress!

immanuelv · Answer

just simplify

anonymous · Answer

Simplify 100?

immanuelv · Answer

sqrt of 100 = 10

anonymous · Answer

Oh-! Okay, thank you! would I add that to 2i then? or.. I think 2i cancels out?

immanuelv · Answer

hold on i got $$x = -30 \pm \frac{ \sqrt{-1210} }{10 }$$

immanuelv · Answer

it will be 11i sqrt 10

anonymous · Answer

How did you get that??

immanuelv · Answer

quadratic formula

anonymous · Answer

$$5x^2 = -30x - 65\
5x^2+30x+65=0\
x^2+6x+13=0$$ would be a good start

anonymous · Answer

then since $6$ is even, it  would be easiest to complete the square an ignore the formula 
$$x^2+6x+13=0\
x^2+6x=-13\
(x+3)^2=-13+9=-4$$

anonymous · Answer

you get 
$$x+3=\pm\sqrt{-4}=\pm2i$$

anonymous · Answer

making
$$x=-3\pm 2i$$

anonymous · Answer

which is exactly what you had got in your first answer, if you divide each term by $10$

anonymous · Answer

Oh thank you, that makes more sense!!