few_shots: 
Example 1:
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.

Example 2:
Concept/skill: 
Understand that the graph of an equation in two variables is the set of all its solutions plotted in the coordinate plane, often forming a curve (which could be a line).

Problem/activity:
Task
Solve the quadratic equation
$$ x^2 = (2x - 9)^2 $$
using as many different methods as possible.


Answer: 
No. This task does not involve an equation in two variables. There is only one variable, x.

Example 3:
Concept/skill: 
Construct a tangent line from a point outside a given circle to the circle.

Problem/activity:
Task
Suppose $A$ is an angle with vertex $P$, as pictured below:
[IMG]
Draw a circle with center $P$ and with  radius $r \gt 0$.  Explain why the circle
meets each ray of angle $A$ in a single point.  Label these points $Q$ and $R$ respectively.
Draw circles with centers $Q$ and $R$ respectively and radius $r$.  These circles meet at $P$ and a second point to be labelled $B$.
Show that ray $\overrightarrow{PB}$  bisects angle $P$.


Answer: 
No. This task does not involve drawing lines that are tangent to circles. The only line that may be drawn is the ray between points P and B.

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

im_task_000870_neg_0

HS_1

im_task_001160_neg_0

HS_2
standard_description: Generate measurement data by measuring lengths of several objects to the nearest whole unit, or by making repeated measurements of the same object. Show the measurements by making a line plot, where the horizontal scale is marked off in whole-number units.
problem_activity: Narrative
The purpose of this activity is for students to learn stage 3 of the Capture Squares center. Capture Squares was introduced in grade 1. In this stage, students spin to get a number (6
–
10) and flip a card (0
–
10) and find the value of the sum. The spinner includes a wild space where students can choose their own number. They find the value of the sum on the game board and connect 2 dots that are adjacent to the number. If that line closes the square, they capture it and shade it in their color. The player to shade in 3 squares first is the winner.
Required Materials
Materials to Gather
Colored pencils or crayons
Number cards 0–10
Paper clips
Materials to Copy
Capture Squares Stage 3 Gameboard
Capture Squares Stage 3 Spinner
Launch
Groups of 2
Give each pair of students a copy of the game board, the spinner and a paper clip, a set of cards, and access to crayons or colored pencils.
“We are going to play a game.”
Spin the spinner and draw a card.
“How could I find the value of the sum of these two numbers?”
30 seconds: quiet think time
1 minute: partner discussion
Share responses.
Use a suggested method or select a volunteer to show how to find the value.
“Now, I find the square that has the value of my sum. I draw a line connecting two dots on that square.”
“If the spinner lands on the wild space, you can pick any number to be one of your addends.”
Repeat 1–2 more times, as needed.
“If I draw the line that completes the square, I shade in that square with my color. The first player to shade in 3 squares is the winner.”
Activity
12 minutes: partner work time
Monitor for a variety of student strategies to share in the synthesis.
Activity Synthesis
Invite selected students to share their strategies.
“When the spinner landed on the wild spot, how did you decide what number to pick?”


aligns: no