M3.9.2 For the adult
All four quarters of the grid
What if the place I want is to the left of the start, or below it?
What this chapter teaches
A grid has four quarters. A negative first number means left of the origin and a negative second number means below it. Each number moves the point on its own. When the sides of a square run along the grid lines, its fourth corner matches one corner across and another corner up.
Three questions to ask
There is no one right wording. Listen for the idea.
- In which quarter is the point (−3, 4)?
- How can you find the fourth corner of a square from three corners?
- What is the difference between the points (−3, 4) and (3, −4)?
After the chapter, the learner can
- Plot points with negative coordinates, like (−2, 3)
- Find the fourth corner of a square from three corners
What they copy into their notebook
Left of the origin is negative across. Below the origin is negative up. The axes make four quarters. Each number moves the point by itself.