few_shots: 
Example:
Concept/skill: 
Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

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


Answer: 
Yes. An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation.

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_pos_0

HS_0
standard_description: Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decomposition by a drawing or equation (e.g., 18 = 10 + 8); understand that these numbers are composed of ten ones and one, two, three, four, five, six, seven, eight, or nine ones.
problem_activity: Stage 2: Numbers 11–19
Required Preparation
Materials to Gather
Connecting cubes
Two-color counters
Materials to Copy
Blackline Masters
Make or Break Apart Numbers Stage 2 Recording Sheet
Make or Break Apart Numbers Stage 2 Number Mat 11-19
Make or Break Apart Numbers Stage 2 Gameboards

Narrative
Students roll to get a number from 11–19. They find two groups of dots that can be put together to make that number. Students write an expression to represent the two parts that make the number.


aligns: yes