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


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

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: Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
problem_activity: Narrative
The purpose of this activity is for students to choose from activities that offer practice working with two-digit numbers. Students choose from any stage of previously introduced centers.
Target Numbers
Five in a Row
Get Your Numbers in Order
Required Materials
Materials to Gather
Materials from previous centers
Required Preparation
Gather materials from:
Target Numbers, Stages 1–3
Five in a Row, Stages 1–6
Get Your Numbers in Order, Stage 1
Launch
Groups of 2
“Now you are going to choose from centers we have already learned.”
Display the center choices in the student book.
“Think about what you would like to do.”
30 seconds: quiet think time
Activity
Invite students to work at the center of their choice.
10 minutes: center work time
Student Facing
Choose a center.
Target Numbers
[IMG]
Five in a Row
[IMG]
Get Your Numbers in Order
[IMG]
Activity Synthesis
Display numbers 2, 1, and 6.
“Mai is playing Target Numbers. Her last sum was 78. These are the numbers she rolled on her last round. Which number should she choose as her tens and which should she choose as her ones in order to get as close to 95 as possible? Why?”


aligns: yes