Explain the statement 3-5 sentences : correspondence is a relation of connection

you may give examples to explain the ideas

If x=-3 is the only x-intercept of the graph of a quadratic equation, which statement best discribes the discriminant of the equation?

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?  

The longer leg of a 30° 60° 90° triangle is 16 times square root of three how long is a shorter leg