How does the equation change when the radius changes? Unlike h and k, why is r always positive?

The radius is a distance, namely; it is the distance from the center to the outside of the circle, and thus it cannot be negative, or the circle would not exist in our dimension, if I do say so myself! The equation's answer increases or decreases, depending on how the radius increases or decreases.

Step-by-step explanation:

f(x) = y

f(-3) = -5

step-by-step explanation:

when rotating a figure 180 degrees, imagine that you are able to take the figure and turn it clockwise or counterclockwise around a center point. to rotate a figure 180 degrees, you will need to apply the rule (x, y) → (-x, -y). start by using a coordinate grid with coordinates for each vertex of the figure. the center point of the coordinate grid is located at (0, 0), which is what you will rotate the figure around. write down the original coordinates of the shape you are going to rotate. then, apply the rule. for example, coordinate (1, 2) becomes (-1, -2). another example would be, coordinate (-4, -2) becoming (4, 2). after you change each original coordinate to the rotated coordinate, you will draw your new figure.

step-by-step explanation: