M4.8.8 For the adult
Word problems and regions
A yard has hens and goats: 30 heads and 84 legs. How many of each?
What this chapter teaches
A word problem becomes two equations: name the unknowns, write each fact as an equation, solve, and check against the words. An inequality in x and y is a region of the graph: a solid boundary includes its line and a dashed one does not.
Three questions to ask
There is no one right wording. Listen for the idea.
- What two facts give the two equations in the hens and goats problem?
- How do you decide which side of a boundary line to hatch?
- What is the difference between a solid and a dashed boundary?
After the chapter, the learner can
- Write two equations from a word problem and solve them
- Shade the region on a graph that fits two inequalities
What they copy into their notebook
Name the unknowns, write a fact as each equation, solve, check in the words. For a region: solid for ≤ and ≥, dashed for < and >, and test a point.