6-A-1-1


6.A.1.1 Plot integer- and rational-valued (limited to halves and fourths) ordered-pairs as coordinates in all four quadrants and recognize the reflective relationships among coordinates that differ only by their signs.


In a Nutshell

This objective expands on previous knowledge using whole numbers to plot ordered pairs.  Halves and fourths are added to either the x or y coordinate resulting in points that do not fall on the grid intersections of the graph. Knowledge of horizontal and vertical number lines provides the foundation for understanding how to plot these points within the grid squares. Negative and positive values of the same numeral are opposites.  For example, the ordered pair (-4, 1) in the second quadrant is a reflection across the x-axis of the ordered pair (-4,-1) in the third quadrant.

Student Actions

Teacher Actions

  • Develop procedural fluency by plotting ordered pairs in all four quadrants, and identify Q1 points as (+, +), Q2 points as (-, +), Q3 points as (-,-), and Q4 points as (+, -).

  • Continue to develop a deep understanding of vertical and horizontal number lines when using the coordinate grid, moving in the appropriate direction and plotting points that include halves and fourths.

  • Build procedural fluency by engaging students in plotting ordered pairs in all four quadrants. (Ex: Move along a life size grid with tile floor lines or tape on floor to graph points in all four quadrants)

  • Use evidence of student thinking to engage students in discussion about why opposite numbers will reflect across either the x- or y-axis.

     

Key Understandings

Misconceptions

  • Ordered pairs must be graphed by first locating the x coordinate, then the y coordinate.

  • Halves and fourths can be represented between grid lines on a graph or in the squares created by those lines.

  • Changing one coordinate (either the x or the y) in an ordered pair to the opposite sign creates a reflection.
  • Which is the x and which is the y coordinate.

  • Positive and negative directions.

  • The x- and y-axes.

  • That points must be plotted on grid intersections.

 


OKMath Framework Introduction

6th Grade Introduction