few_shots: 
Example:
Concept/skill: 
Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.

Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Answer: 
No. This problem does not directly teach how side ratios in right triangles lead to definitions of trigonometric ratios. Instead, it involves solving a trigonometric function.

Now, determine whether the following problem or activity can enable students to understand the concepts or skills in the provided description.

shot_info: fl_problem_001894_neg_0

HS_0
standard_description: Apply and extend previous understandings of addition and subtraction to add and subtract rational numbers; represent addition and subtraction on a horizontal or vertical number line diagram.
problem_activity: Activity
In this activity students continue to build fluency operating with signed numbers as they match different expressions that have the same value. Students look for and use the relationship between inverse operations (MP7).
As students work, identify groups that make connections between the operations, for example they notice that subtracting a number is the same as adding its opposite, or that dividing is the same as multiplying by the multiplicative inverse.
Launch
Arrange students in groups of 2. Distribute pre-cut slips from the blackline master.
Student Facing
Your teacher will give you a set of cards. Group them into pairs of expressions that have the same value.
Student Response
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Anticipated Misconceptions
If students struggle to find matches, encourage them to think of the operations in different ways. You might ask:
How else can you think of ____ (subtraction, addition, multiplication, division)?
Activity Synthesis
Select students to share their strategies. Highlight stategies that compared the structure of the expressions instead of just the final answers.
Discuss:
Subtracting a number is equivalent to adding the additive inverse.
A number and its additive inverse have oppostie signs (but the same magnitude).
Dividing by a number is equivalent to multiplying by the multiplicative inverse.
A number and its multiplicative inverse have the same sign (but different magnitudes).
If desired, have students order their pairs of equivalent expressions from least to greatest to review ordering rational numbers.
Engagement: Develop Effort and Persistence.
Break the class into small discussion groups and then invite a representative from each group to report back to the whole class.
Supports accessibility for: Attention; Social-emotional skills
Speaking, Representing: MLR7 Compare and Connect.
Use this routine to support whole-class discussion. Ask students to consider what is the same and what is different about the structure of each expression. Draw students’ attention to the association between quantities (e.g., adding the additive inverse is subtracting; multiplying by the multiplicative inverse is dividing). These exchanges strengthen students’ mathematical language use and reasoning to describe when comparing inverse-operation relationships involving rational numbers.
Design Principle(s): Support sense-making; Maximize meta-awareness


aligns: no