Which of the following functions is quadratic?

Read the situations in the table below. then drag a graph and equation to represent each situation. indicate whether each of the relationships is proportional or non-proportional. edit : i got the right answer its attached

Use the elimination method to solve the systems of equations.choose the correct ordered pair. 7x+4y=39

Acyclist bike x distance at 10 miles per hour .and returns over the same path at 8 miles per hour.what is the cyclist average rate for the round trip in miles per hour ?