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, assess whether the following problem or activity is 'aligned' with the given Common Core standard in Mathematics.

shot_info: fl_problem_001894_pos_0

HS_0
standard_description: Find the inverse of a matrix if it exists and use it to solve systems of linear equations (using technology for matrices of dimension 3 × 3 or greater).
problem_activity: Stage 2: Describe the Flat Shape
Required Preparation
Materials to Gather
Play dough or modeling clay
Straws
Materials to Copy
Blackline Masters
Build Shapes Stage 1 and 2 Cards

Narrative
Students choose a shape card and describe the shape to their partner, who builds the shape based on the description.
Additional Information
Bag of straws per group of 2 students:
At least 6 straws in each size:
\(\frac{1}{2}\)
inch
1 inch
\(1 \frac{1}{2}\)
inch
\(2 \frac{3}{4}\)
inches


aligns: no