What is the domain of this function

What is the solution set of the quadratic inequality x^2-5< or equal to 0

The price of a visit to the dentist is calculated according to the formula 50+100n50+100n where nn is the number of cavities the dentist finds. on your last visit to the dentist, 22 cavities were found. what was the cost of your visit?

Which of the following constants can be added to x2 - 3x to form a perfect square trinomial?