few_shots: 
Example:
Concept/skill: 
Prove that, given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solutions.

Problem/activity:
Problem 1
The table below contains single equations in a single variable, single equations in two variables, and pairs of simultaneous equations in two variables. Check the appropriate box to show whether there is no solution, exactly 1 solution, or if there is an infinite number of solutions.
|                                                          | **           No solution          ** | **           Exactly 1 solution          ** | **           Infinite number of solutions          ** |
|----------------------------------------------------------|--------------------------------------|---------------------------------------------|-------------------------------------------------------|
|                       $${9=4x+7}$$                       |                                      |                                             |                                                       |
|                       $${y=3y+5}$$                       |                                      |                                             |                                                       |
|                    $${y={x\over2}}$$                     |                                      |                                             |                                                       |
|                     $${3x+6y-9=0}$$                      |                                      |                                             |                                                       |
|    $${x=y}$$                        $${1.25x=1.25y}$$    |                                      |                                             |                                                       |
| $${9.9=6x+8y}$$                        $${9x=2.5y-8.8}$$ |                                      |                                             |                                                       |
| $${11x-2y=1.5}$$                        $${11x-2y=2.5}$$ |                                      |                                             |                                                       |
Problem 2
Kim has a small container and a large container as shown.
[IMG]
It takes 16 of the small containers to fill the large container. Three small containers leave 1.95 gallons of space in the big container.
What is the size of each of the two containers?


Answer: 
No. Completing neither of these problems requires replacing one equation by the sum of that equation and a multiple of the other equation.

Now, determine whether the following problem or activity can enable students to understand the concepts or skills in the provided description.

shot_info: fl_problem_001392_neg_0

8
standard_description: Approximate the probability of a chance event by collecting data on the chance process that produces it and observing its long-run relative frequency, and predict the approximate relative frequency given the probability. For example, when rolling a number cube 600 times, predict that a 3 or 6 would be rolled roughly 200 times, but probably not exactly 200 times.
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
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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: no