few_shots: 
Example 1:
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.

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


Concept/skill: 
Solve quadratic equations in one variable.

Answer: 
Yes. This task shows one quadratic equation with one variable, x.

Example 3:
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 $P$.


Concept/skill: 
Make formal geometric constructions with a variety of tools and methods (compass and straightedge, string, reflective devices, paper folding, dynamic geometric software, etc.). Copying a segment; copying an angle; bisecting a segment; bisecting an angle; constructing perpendicular lines, including the perpendicular bisector of a line segment; and constructing a line parallel to a given line through a point not on the line.

Answer: 
Yes. This task asks students to draw a ray that bisects an angle. The act of drawing circles and rays may involve compass and straightedge or dynamic geometric software.

Now, does the problem or activity shown below enable students to learn the full intent of the following concept or skill?

shot_info: fl_problem_001894_pos_0

HS_0

im_task_000870_pos_0

HS_1

im_task_001160_pos_0

HS_2
standard_description: Fluently add and subtract multi-digit whole numbers using the standard algorithm.
Grade 4 expectations in this domain are limited to whole numbers less than or equal to 1,000,000.
problem_activity: Narrative
The purpose of this activity is for students to facilitate the Estimation Exploration they created in the previous activity for another group in the class. Each group should be paired with another group and they will take turns facilitating their Estimation Exploration for the other group. If time allows, students could facilitate their Estimation Exploration with more than 1 group.
MLR8 Discussion Supports.
At the appropriate time, give students 2–3 minutes to make sure that everyone in their group can explain their Estimation Exploration activity. Invite groups to rehearse what they will say when they share with the whole class.
Advances: Speaking, Conversing, Representing
Required Materials
Materials to Gather
Chart paper
Colored pencils, crayons, or markers
Launch
Groups of 3 or 4
Give each group a piece of chart paper and a marker to record responses.
“Pair up with another group in the class. Each group will present their Estimation Exploration.”
Activity
10–12 minutes: small-group work time
Remind students to switch roles halfway through the time allowed.
Student Facing
Display your image for your classmates.
Ask them, “What is an estimate that’s too high?” “Too low?” “About right?”
Give them a minute of quiet think time.
Give them a minute to discuss together.
Have them share estimates.
Record their ideas.
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Activity Synthesis
“What did you learn as you presented your Estimation Exploration?” (I learned that ranges of estimates might be bigger than you expect. I learned that it’s important to understand the size of the items you are trying to estimate or be familiar with it, otherwise you cannot make good estimates.)


aligns: no