See picture.
We can't give "steps" that will lead you to a solution without know what you can do or understand about these problems. And we could best learn this by seeing what you have attempted yourself. Do you, for example, know that if $\displaystyle \alpha$ and $\displaystyle \beta$ are roots of $\displaystyle ax^2+ bx+ c= 0$ the $\displaystyle ax^2+ bx+ c= a(x- \alpha)(x- \beta)$? Do you know the quadratic formula?
What is $\displaystyle \dfrac{-b+\sqrt{b^2- 4ac}}{2a}+ \dfrac{-b- \sqrt{b^2- 4ac}}{2a}$?
What is $\displaystyle \left(\dfrac{-b+\sqrt{b^2- 4ac}}{2a}\right)\left(\dfrac{-b- \sqrt{b^2- 4ac}}{2a}\right)$?
That is exactly what this problem is asking you to do. Why have you not done it?
(You do know that $\displaystyle (a- b)(a+ b)= a^2- b^2$, don't you?)