few_shots: Example 1:
Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Mathematical concept/skill options: 
A. Prove and apply trigonometric identities.
B. Model periodic phenomena with trigonometric functions.
C. Interpret functions that arise in applications in terms of the context.
D. Build a function that models a relationship between two quantities.
E. Define, evaluate, and compare functions.
F. Use functions to model relationships between quantities.
G. Understand the concept of a function and use function notation.
H. Analyze functions using different representations.
I. Extend the domain of trigonometric functions using the unit circle.
J. Interpret expressions for functions in terms of the situation they model.
K. Build new functions from existing functions.
L. Construct and compare linear and exponential models and solve problems.


Your response:
Thought: This problem applies trigonometric identities, including the angle addition formula for cosine.
Answer: A

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


Mathematical concept/skill options: 
A. Apply and extend previous understandings of arithmetic to algebraic expressions.
B. Write expressions in equivalent forms to solve problems.
C. Understand solving equations as a process of reasoning and explain the reasoning.
D. Use the four operations with whole numbers to solve problems.
E. Generate and analyze patterns.
F. Understand and apply properties of operations and the relationship between addition and subtraction.
G. Use properties of operations to generate equivalent expressions.
H. Solve real-life and mathematical problems using numerical and algebraic expressions and equations.
I. Represent and analyze quantitative relationships between dependent and independent variables.
J. Understand properties of multiplication and the relationship between multiplication and division.
K. Work with equal groups of objects to gain foundations for multiplication.
L. Represent and solve problems involving multiplication and division.
M. Solve problems involving the four operations, and identify and explain patterns in arithmetic.
N. Work with radicals and integer exponents.
O. Interpret the structure of expressions.
P. Solve equations and inequalities in one variable.
Q. Understand addition as putting together and adding to, and understand subtraction as taking apart and taking from.
R. Multiply and divide within 100.
S. Represent and solve problems involving addition and subtraction.
T. Use polynomial identities to solve problems.
U. Represent and solve equations and inequalities graphically.
V. Understand the connections between proportional relationships, lines, and linear equations.
W. Reason about and solve one-variable equations and inequalities.
X. Rewrite rational expressions.
Y. Understand the relationship between zeros and factors of polynomials.
Z. Perform arithmetic operations on polynomials.
AA. Create equations that describe numbers or relationships
AB. Analyze and solve linear equations and pairs of simultaneous linear equations.
AC. Gain familiarity with factors and multiples.
AD. Write and interpret numerical expressions.
AE. Add and subtract within 20.
AF. Work with addition and subtraction equations.
AG. Solve systems of equations.
AH. Analyze patterns and relationships.


Your response:
Thought: This task asks students to solve an equation in one variable. Since the problem asks for many different solution methods, students are also encouraged to solve the problem graphically.
Answer: P, U

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 $P$.


Mathematical concept/skill options: 
A. Apply trigonometry to general triangles.
B. Understand similarity in terms of similarity transformations.
C. Analyze, compare, create, and compose shapes.
D. Prove geometric theorems.
E. Make geometric constructions.
F. Graph points on the coordinate plane to solve real-world and mathematical problems.
G. Understand congruence and similarity using physical models, transparencies, or geometry software.
H. Understand congruence in terms of rigid motions.
I. Draw, construct, and describe geometrical figures and describe the relationships between them.
J. Translate between the geometric description and the equation for a conic section.
K. Reason with shapes and their attributes.
L. Prove theorems involving similarity.
M. Explain volume formulas and use them to solve problems.
N. Find arc lengths and areas of sectors of circles.
O. Define trigonometric ratios and solve problems involving right triangles.
P. Use coordinates to prove simple geometric theorems algebraically.
Q. Visualize relationships between two-dimensional and three-dimensional objects.
R. Solve real-life and mathematical problems involving angle measure, area, surface area, and volume.
S. Understand and apply theorems about circles.
T. Identify and describe shapes (squares, circles, triangles, rectangles, hexagons, cubes, cones, cylinders, and spheres).
U. Solve real-world and mathematical problems involving volume of cylinders, cones, and spheres.
V. Classify two-dimensional figures into categories based on their properties.
W. Apply geometric concepts in modeling situations.
X. Solve real-world and mathematical problems involving area, surface area, and volume.
Y. Experiment with transformations in the plane.
Z. Understand and apply the Pythagorean Theorem.
AA. Draw and identify lines and angles, and classify shapes by properties of their lines and angles.


Your response:
Thought: This task asks students to make geometric constructions, such as bisecting an angle.
Answer: E

Now, assign the following problem or activity to one or more relevant mathematical concepts/skills it teaches.
shot_info: fl_problem_001894

HS_0

im_task_000870

HS_1

im_task_001160

HS_2
options: Use coordinates to prove simple geometric theorems algebraically.

Reason with shapes and their attributes.

Identify and describe shapes (squares, circles, triangles, rectangles, hexagons, cubes, cones, cylinders, and spheres).

Apply geometric concepts in modeling situations.

Understand congruence in terms of rigid motions.

Understand similarity in terms of similarity transformations.

Experiment with transformations in the plane.

Explain volume formulas and use them to solve problems.

Visualize relationships between two-dimensional and three-dimensional objects.

Understand and apply theorems about circles.

Graph points on the coordinate plane to solve real-world and mathematical problems.

Find arc lengths and areas of sectors of circles.

Analyze, compare, create, and compose shapes.

Solve real-world and mathematical problems involving area, surface area, and volume.

Apply trigonometry to general triangles.

Solve real-life and mathematical problems involving angle measure, area, surface area, and volume.

Translate between the geometric description and the equation for a conic section.

Understand and apply the Pythagorean Theorem.

Understand congruence and similarity using physical models, transparencies, or geometry software.

Define trigonometric ratios and solve problems involving right triangles.

Draw and identify lines and angles, and classify shapes by properties of their lines and angles.

Make geometric constructions.

Prove theorems involving similarity.

Draw, construct, and describe geometrical figures and describe the relationships between them.

Classify two-dimensional figures into categories based on their properties.

Solve real-world and mathematical problems involving volume of cylinders, cones, and spheres.

Prove geometric theorems.
problem_activity: Activity
Students observe that the angle formed by connecting endpoints of a diameter to a third point on the circle appears to be a right angle. They confirm that this is true for a few particular points, then write a conjecture. This conjecture will be generalized in an upcoming unit.
Monitor for different ways that students word the conjecture to highlight during the discussion. Listen for terms such as
diameter
,
endpoints
,
right triangle
, and
right angle
. The term
chord
will be defined in a subsequent unit. It is not necessary to define it here.
This activity works best when each student has access to devices that can use the embedded applet because students will benefit from seeing the relationship in a dynamic way. If students don’t have individual access, projecting the applet would be helpful during the synthesis.
Digital
Launch
Arrange students in groups of 4. Provide access to internet-enabled devices, ideally one per group. Distribute one index card with each internet-enabled device.
Conversing: MLR2 Collect and Display.
As students work on this activity, listen for and collect the language students use to justify why the angle formed by segments
\(BD\)
and
\(CD\)
is a right angle. Write the students’ words and phrases on a visual display. As students review the visual display, ask them to revise and improve how ideas are communicated. For example, a phrase such as, “The lines make 90 degrees because they have opposite slopes” can be improved by restating it as “Segments
\(BD\)
and
\(CD\)
are perpendicular because their slopes are opposite reciprocals.” This will help students use the mathematical language necessary to precisely justify why the measure of the angle formed by segments
\(BD\)
and
\(CD\)
is 90 degrees.
Design Principle(s): Optimize output (for justification); Maximize meta-awareness
Student Facing
Use the applet to answer the questions.
First, observe and describe the image:
What kind of line is
\(BC\)
in reference to the circle?
What does the measurement of angle
\(BDC\)
appear to be?
Move point
\(D\)
around. How does the measurement of angle
\(BDC\)
appear to change? Use a corner of the index card to compare the size of the angle as it moves.
Move point
\(D\)
to a location with integer coordinates. Each student in the group should choose a different spot for
\(D\)
. Calculate the slopes of segments
\(BC\)
and
\(BD\)
. What do your results tell you?
Now select the button labeled “slopes.” This will show the slopes of
\(BD\)
and
\(BC\)
and their product. Move point
\(D\)
around. What do you notice about the product of the slopes?
Based on the results, write a conjecture that captures what you are seeing.
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Print
Launch
Arrange students in groups of 4.
Conversing: MLR2 Collect and Display.
As students work on this activity, listen for and collect the language students use to justify why the angle formed by segments
\(BD\)
and
\(CD\)
is a right angle. Write the students’ words and phrases on a visual display. As students review the visual display, ask them to revise and improve how ideas are communicated. For example, a phrase such as, “The lines make 90 degrees because they have opposite slopes” can be improved by restating it as “Segments
\(BD\)
and
\(CD\)
are perpendicular because their slopes are opposite reciprocals.” This will help students use the mathematical language necessary to precisely justify why the measure of the angle formed by segments
\(BD\)
and
\(CD\)
is 90 degrees.
Design Principle(s): Optimize output (for justification); Maximize meta-awareness
Student Facing
The image shows a circle with several points plotted on the circle.
[IMG]
What kind of segment is
\(BC\)
in reference to the circle?
Choose one of the plotted points on the circle and call it
\(D\)
. Each student in the group should choose a different point. Draw segments
\(BD\)
and
\(DC\)
. What does the measure of angle
\(BDC\)
appear to be?
Calculate the slopes of segments
\(BD\)
and
\(DC\)
. What do your results tell you?
Compare your results to those of others in your group. What did they find?
Based on your group’s results, write a conjecture that captures what you are seeing.
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
Ask previously identified groups to share their conjectures. Challenge students to decide whether all the conjectures are saying the same thing, and if any of the conjectures need to be refined. Encourage students to respectfully disagree, ask for clarification, or point out contradicting information.
There are many ways to correctly word the conjecture. As students work to refine the wording, be sure that the word
diameter
is included, that it’s clear that 2 points are at the endpoints of the diameter, and that the third point is clearly somewhere else on the circle. Students may describe the result as 2 segments that form a right angle or 3 segments that form a right triangle.
Once the conjecture is finalized, ask students if they have proven it (they have not; they’ve just shown it’s true for a few particular cases). Tell students that we will look at a more general case of this assertion in an upcoming unit.
Action and Expression: Develop Expression and Communication.
Invite students to talk about their ideas with a partner. Display sentence frames, such as: “How did you develop your conjecture?” and “I chose this conjecture because. . . .” to support students when they explain their ideas.
Supports accessibility for: Language; Organization


correct_option_index: 0

9