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: Describe objects in the environment using names of shapes, and describe the relative positions of these objects using terms such as above, below, beside, in front of, behind, and next to.
problem_activity: Narrative
The purpose of this activity is for students to identify shapes as flat and solid as they sort shapes into groups. A sorting task gives students opportunities to analyze the structure of the shapes and identify common properties and characteristics (MP7).
If the sorting mat provided in the student workbook is too small for students to sort the shapes, consider giving students two pieces of construction paper, or ask students to put the solid shapes on one side of the table and the flat shapes on the other side.
MLR8 Discussion Supports.
Invite each partner to identify each shape aloud: Flat shape or solid shape. Encourage students to challenge each other when they disagree.
Advances: Conversing
Action and Expression: Internalize Executive Functions.
Invite students to plan a strategy for how they will sort the shapes.
Supports accessibility for: Conceptual Processing, Organization
Required Materials
Materials to Gather
Geoblocks
Solid shapes
Materials to Copy
Flat Shapes Cards K
Required Preparation
Each group of 2 needs a set of solid shapes and a set of cards.
Launch
Groups of 2
Give each group of students a set of solid shapes and a set of flat shapes cards.
Activity
“Work with your partner to sort the shapes into two groups. Write a number to show how many shapes are in each group.”
3 minutes: partner work time
“Pair up with another group. Show them how you sorted your shapes. Did you sort all of the shapes in the same way?”
3 minutes: small-group work time
“What could you call each group of shapes to show why you put those shapes together?”
Monitor for a group that sorts by flat shapes and solid shapes.
Student Facing
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[IMG]
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Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Advancing Student Thinking
If students identify a pyramid as flat because “it looks like a triangle,” consider asking:
“What is the same about all of the shapes in this group?”
Display a pyramid and a triangle next to each other and ask “What do you notice about these shapes? What is different about them?”
Activity Synthesis
Invite previously selected students to share the way they sorted the shapes into flat shapes and solid shapes.
“This group has flat shapes. This group has solid shapes.”
Display a square.
“Should this shape go with the flat shapes or the solid shapes? Why?” (It is a flat shape. If we put it on our desk, it doesn’t stick up.)
Display a cube.
“Should this shape go with the flat shapes or the solid shapes? Why?” (It is a solid shape. It sticks up and takes up space.)


aligns: no