standard_description: Use a pair of perpendicular number lines, called axes, to define a coordinate system, with the intersection of the lines (the origin) arranged to coincide with the 0 on each line and a given point in the plane located by using an ordered pair of numbers, called its coordinates. Understand that the first number indicates how far to travel from the origin in the direction of one axis, and the second number indicates how far to travel in the direction of the second axis, with the convention that the names of the two axes and the coordinates correspond (e.g., x-axis and x-coordinate, y-axis and y-coordinate).
problem_activity: Problem 1
Someone sorted some shapes as shown below.
[IMG]
a.   What is similar about the two groups of figures? What term(s) can we use to describe all of the shapes?
b.   What is different about the two groups of shapes?
Problem 2
Decide whether each of the following statements are true or false. If it is false, rewrite the statement so that it is true.
a.   A trapezoid is always a quadrilateral.
b.   A quadrilateral is never a trapezoid.


aligns: no