Ikeep getting stuck on these kind of questions, do i expand or try and factorise

Use the graph to determine the range. which notations accurately represent the range? check all that apply. (–∞, 2) u (2, ∞) (–∞, –2) u (–2, ∞) {y|y ∈ r, y ≠ –2} {y|y ∈ r, y ≠ 2} y < 2 or y > 2 y < –2 or y > –2

Ahovercraft takes off from a platform. its height (in meters), xx seconds after takeoff, is modeled by: h(x)=-2x^2+20x+48h(x)=−2x 2 +20x+48 what is the maximum height that the hovercraft will reach?

Which expression equals 9^3 sqrt 10 a. 5 sqrt 10 + 4 sqrt 10 b. 5^3 sqrt 10 + 4 ^3 sqrt 10 c. 5 sqrt 10 + 4^3 sqrt 10 d. 5^3 sqrt 10 + 4 sqrt 10