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


Concept/skill: 
Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.

Answer: 
No. This problem does not directly teach how side ratios in right triangles lead to definitions of trigonometric ratios. Instead, it involves solving a trigonometric function.

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 following problem or activity enable students to learn the full intent of the following concept or skill?

shot_info: fl_problem_001894_neg_0

HS_0

im_task_000870_pos_0

HS_1

im_task_001160_pos_0

HS_2
standard_description: Know that straight lines are widely used to model relationships between two quantitative variables. For scatter plots that suggest a linear association, informally fit a straight line, and informally assess the model fit by judging the closeness of the data points to the line.
problem_activity: Optional activity
Students interpret the slope and intercepts in the context of the situation. They also discuss limitations of the mathematical model.
This activity can be extended by having students investigate if temperature on other continents or across continents fits the same pattern that we found for North America.
Launch
Keep students in same groups of 3–4.
Student Facing
Refer to your equation for the line that models the association between latitude and temperature of the cities.
What does the slope mean in the context of this situation?
Find the vertical and horizontal intercepts and interpret them in the context of the situation.
Can you think of a city or a location that could not be represented using this same model? Explain your thinking.
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Anticipated Misconceptions
Students may want to say “For every one unit increase in
\(x\)
,
\(y\)
decreases by 1.07 units.” Ask them to use the specific units and quantities in the model, latitude in degrees north and temperature in degrees Fahrenheit.
Activity Synthesis
Invite students to share their responses. Discuss the limitations and uses of the model. Consider asking the following questions:
“What are some limitations of the model?”
“Do limitations mean that the model is not good?” (No, it just means that we have to be aware of when we can use it and when we can’t use it. Our model is pretty good for latitudes between 25 and 65 degrees north, and for locations in North America.)
“What questions do you have about predicting temperature?”
“How could you extend your investigation of predicting temperature or the weather?”
Engagement: Develop Effort and Persistence.
Break the class into small discussion groups and then invite a representative from each group to report back to the whole class.
Supports accessibility for: Language; Social-emotional skills; Attention


aligns: yes