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: Problem 1
Explain how you know the expressions in Column A are equivalent to the expressions in Column B.
| **           Column A          ** | **           Column B          ** |
|-----------------------------------|-----------------------------------|
|           $${-3(x+4)}$$           |           $${-3x-12}$$            |
|           $${(4+x)+3}$$           |           $${x+(4+3)}$$           |
|           $${(x+4)-3}$$           |          $${-3+(x+4)}$$           |
Problem 2
Explain the properties of operations that were used to transform
$${a(x-y)}$$
to the equivalent expression,
$${-(ay-ax)}$$
.
Problem 3
If the expression
$${\frac{x}{2} + \frac{3}{4}}$$
is multiplied by
$$4$$
, the expression
$${{2x+3}}$$
results.
Is
$${{2x+3}}$$
an equivalent expression to
$${\frac{x}{2} + \frac{3}{4}}$$
?


aligns: no