What is the solution to the inequality below? i think its b but im not shour

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Cole says the distance between points (-5,0) and (0,-5)is 5 units. is he correct? explain why or why not.

On friday, there were x students at the baseball game. on monday, there were half as many students at the game as there were on friday. on wednesday, there were 32 fewer students at the game as there were on friday. which expression could represent the total number of tickets sold for all 3 games?