Describe the relationship between x and y

The relationship between x and y is called a linear relationship because the points so plotted all lie on a single straight line

Sorry this isn’t really an answer i just need to answer two questions. i hope that you find the answer that your looking for though

You're asking in the ap section, so i'll give the ap calculus-style answer. alternatively, you can find the vertex of the parabola and use the "y"-coordinate as the answer.

the maximum height can occur at a critical number, that is, a number  such that  .

the derivative of  can be calculated as follows:



find a value of  that is a zero of the derivative:


this is parabola that is opening downward; we can assume there is a maximum at  .

to find that maximum, calculate  .