Dynact
From Wiki2
In this chapter, you’ll learn how to solve problems involving more than one equation, like finding out when two animals that grow at different rates will be the same size.
Hi, In case the question submission deadline wasn't yesterday....
I took a look at the resources on the FTP site, "the 3 Chapters of the textbook that represent lesson content for the 3 prototypes" (4.6) and there seems to be a problem with the 3rd. Rational expression and functions has a pdf from a chapter that doesn't cover that material. While it does cover rational exponents, that is a very different topic/content/standard area.
I'll skip it for now but perhaps they might have another chapter reference.