Hello it's due tomorrow and can you explain it to me so i can show my work that would be great!

What is the name used to describe a graph where for some value of x, there exists 2 or more different values of y?

Write an algebraic expression to match each statement a. four less than 8 times a number b. twice the difference of a number and six c. nine from a number squared

Find the value of x for which line a is parallel to line b