Find the value of 4^2+6^2 .20 52 100

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?  

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

Will mark name all segments skew to bc