What’s the answer to the question?

Use the quadratic formula to solve the equation. if necessary, round to the nearest hundredth. x^2 - 20 = x a. 5, 4 b. -5, -4 c. -5, 4 d. 5, -4

Find the value of x. also give me an explanation so i can complete it to other questions as well, : )

What are the domain and range of the function below? a) domain: (-4,0) range: [-2,infinity) b) domain: (-3,0) range: [-2,infinity) c) domain: (-infinity, infinity) range: [-2, infinity) d) domain: [-2,infinity) range: (-infinity, infinity)