I need to find a recursive routine and a explicit equation and then graph it.

The variable z is directly proportional to x, and inversely proportional to y. when x is 4 and y is 13, z has the value 1.2307692307692. what is the value of z when x= 9, and y= 20

12. decide whether each statement is always true, sometimes true, or never true. a. when corresponding points of an original figure and its reflection are connected, the resulting segments are all perpendicular to the line of reflection. b. when a point is reflected over a horizontal line, the y-coordinate of the point stays the same. answer both questions and explain

Which of the following is a justification used while proving the similarity of triangles lom and mon