1. The problem statement, all variables and given/known data Hello! I will be grateful for your help in deciphering the meaning of a paragraph from the book. I honestly don't understand how they got the semi-circle on the xy graph by transferring it from rθ graph. 2. Relevant equations I attach the screen shot from the book. 3. The attempt at a solution (1) if on xy graph values of r are on the x-axis, and values of θ are on the y axis, then when r = 6, we have to plot θ = 0, it's clear and corresponds to the point (6,0); (2) but then when r = 3√2, θ = π/4, and when r = 0, θ = π/2, so I don't understand how could they "finish" the curve at the origin, namely at (0,0)? How that xy curve was formed by transforming values from the rθ curve? Thank you very much!