Question

Melons are spaced 1 meter apart in a square x-y grid. One plant is replaced by an irrigation sprayer. The sprayer covers those plants that satisfy the relationship x2 + y2 <20 meters, with the sprayer at (0,0). What are all the possible x coordinates of plants watered by this sprayer? What are all the possible y coordinates of plants watered by this sprayer? List the possible x-coordinates and the possible y-coordinates as separate sets, and sketch this situation. Is the relationship of x and y a function? Why?

Answer 1

plz help

Answer 2

The equation x^2 + y^2 = 20 is the equation of what figure?
To get the highest and lowest values of y, let x = 0, and solve for y.
To get the highest and lowest values of x, let y = 0, and solve for x.

Answer 3

yeah i mostly get everything but the very last question asking if the relationship between x and y is a function

Answer 4

What is the shape of the graph of the equation of x^2 + y^2 = 20?

Answer 5

circle but what does that have to do with the relationship between x and y and that being a function or not

Answer 6

It has a lot to do with it.
A function is a relation that maps each element of the domain to a single element of the range. In other words, for every x-value in domain, there is only on y-value associated with it as an ordered pair.
For example:
{(1,2), (2, 4), (3, 6), (4, 8)} is a relation that is also a function. Its domain is {1, 2, 3, 4}, and notice that for each element of the domain, there is only one ordered pair.

{(-2, 0), (0, -2), (0, -2), (2, 0)} is a relation that is not a function. The domain is {-2, 0, 2}. Notice that the element of the domain 0 is used in two ordered pairs of the relation. That makes the relation not a function.

In a circle, you must have many pairs of ordered pairs using the same x value. Therefore, every circle is not a function.

There is a way to quickly determine if a relation is a function using its graph. It's called the vertical line test. After you graph the relation in the x-y plane, think of a vertical line scanning the graph, let's say, from left to right. As the vertical line moves across the graph, if at any x-value it intersects more than one point on the graph of the relation, then rthe relation is not a function.

Answer 7

In the example below, as the vertical line moves to the right, at any position, it intersects the relation at only one point. This relation is a function.