standard_description: Determine whether a group of objects (up to 20) has an odd or even number of members, e.g., by pairing objects or counting them by 2s; write an equation to express an even number as a sum of two equal addends.
problem_activity: Triangle
$${{{CDE}}}$$
underwent a transformation that created triangle
$${{{C'D'E'}}}$$
.
[IMG]
a.   Describe how triangle
$${{{CDE}}}$$
was transformed to become triangle
$${{{C'D'E'}}}$$
.
b.   What features stayed the same?
c.   What features changed?
d.   Is triangle
$${{{CDE}}}$$
congruent to triangle
$${{{C'D'E'}}}$$
? Explain how you know.


aligns: no