standard_description: Identify when two expressions are equivalent (i.e., when the two expressions name the same number regardless of which value is substituted into them). For example, the expressions y + y + y and 3y are equivalent because they name the same number regardless of which number y stands for.
problem_activity: Problem 1
Jung's teacher drew a shape on the board (shown below), and asked the students to find the area of the shape. Describe a method Jung could use to find the area and then determine the area.
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Problem 2
Find the area of the trapezoid below in three different ways by:
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a.   Drawing a rectangle around the trapezoid and subtracting the additional area around it
b.   Dividing the trapezoid into two triangles using a diagonal line across the trapezoid
c.   Dividing the trapezoid into two right triangles and a rectangle
Problem 3
Find the area of the triangle in the grid below.
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aligns: no