Did I solve the task correctly?

[grand cloud]

My code:
void main() {
double a = 2.0;
double b = 8.0;
double c = 3.0;

double x1 = (-b + Math.sqrt(b * b - 4.0 * a * c)) / (2.0 * a);
double x2 = (-b - Math.sqrt(b * b - 4.0 * a * c)) / (2.0 * a);

IO.println(x1);
IO.println(x2);

}

[wary igloo]

<@&987246399047479336> please have a look, thanks.

[arctic glade]

Looks good. Small nitpick on the question, a,b,c are called "coefficients" not "prefixes".

[stray dirge]

^ @midnight rivet

[hexed jackal]

just little tips
you could create variable that hold the value of Math.sqrt(b * b - 4.0 * a * c)
so you do not calculate it twice
part of a clean code that you do not repeat yourself
and well done

[grand cloud]

Thanks all

[hexed jackal]

you welcome

[midnight rivet]

Made an issue

On the list to fix