few_shots: Example:
Problem/activity:
For each pair of numbers, determine if the values are equivalent. Explain your reasoning for each one.
a.
$$-0.25$$
and
$$\frac{1}{-4}$$
b.
$$-\left ( \frac{1}{4} \right )$$
and
$$\frac{-1}{-4}$$
c.
$$\frac{-1}{4}$$
and
$$-\frac{1}{4}$$


Mathematical concept/skill options: 
A. Apply and extend previous understandings of operations with fractions to add, subtract, multiply, and divide rational numbers.
B. Reason quantitatively and use units to solve problems.
C. Apply and extend previous understandings of numbers to the system of rational numbers.
D. Represent complex numbers and their operations on the complex plane.
E. Perform arithmetic operations with complex numbers.
F. Compute fluently with multi-digit numbers and find common factors and multiples.
G. Represent and model with vector quantities.
H. Perform operations on vectors.
I. Use properties of rational and irrational numbers.
J. Use complex numbers in polynomial identities and equations.
K. Extend the properties of exponents to rational exponents.
L. Know that there are numbers that are not rational, and approximate them by rational numbers.
M. Perform operations on matrices and use matrices in applications.
N. Apply and extend previous understandings of multiplication and division to divide fractions by fractions.


Your response:
A

Now, assign the following problem or activity to one or more relevant mathematical concepts/skills it teaches.
shot_info: fl_problem_001097

7
options: Define, evaluate, and compare functions.

Model periodic phenomena with trigonometric functions.

Understand the concept of a function and use function notation.

Build a function that models a relationship between two quantities.

Interpret expressions for functions in terms of the situation they model.

Use functions to model relationships between quantities.

Build new functions from existing functions.

Prove and apply trigonometric identities.

Extend the domain of trigonometric functions using the unit circle.

Construct and compare linear and exponential models and solve problems.

Analyze functions using different representations.

Interpret functions that arise in applications in terms of the context.
problem_activity: Activity
In this activity, students find intercepts and slopes for pairs of equations. They should notice that the equations in each pair are multiples of one another and therefore are equivalent equations. Students look for and make use of structure (MP7) when they notice the relationships between the pairs of equations.
Launch
Ask students what they remember about
\(x\)
- and
\(y\)
-intercepts. One useful thing to remember is that the
\(x\)
-intercept of a graph occurs where the
\(y\)
-coordinate is zero. (Demonstrate using a graph, if needed.) So, to find the
\(x\)
-intercept of a graph representing an equation, you can replace
\(y\)
with 0 and solve the equation for
\(x\)
. (And vice versa to find the
\(y\)
-intercept.)
Ask students how they can use two points like
\((1,0)\)
and
\((0,8)\)
to find the slope of a line. (Using a formula like
\(m = \frac{y_2 - y_1}{x_2 - x_1}\)
, or a less-formal version like “subtract the y’s, subtract the x’s, then divide.
”
For this example the slope is -8 since
\(\frac{8 - 0}{0-1} = \text{-}8\)
.)
Student Facing
Here are some equations in pairs. For each equation:
Find the
\(x\)
-intercept and
\(y\)
-intercept of a graph of the equation.
Find the slope of a graph of the equation.
\(x + y = 6\)
and
\(2x + 2y = 12\)
\(3y - 15x = \text{-}33\)
and
\(y - 5x = \text{-}11\)
\(5x + 20y = 100\)
and
\(4x + 16y = 80\)
\(3x - 2y = 10\)
and
\(4y - 6x = \text{-}20\)
What do you notice about the pairs of equations?
Choose one pair of equations and rewrite them into slope-intercept form (
\(y = mx + b\)
). What do you notice about the equations in this form?
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
The purpose of the discussion is to show that equations that are multiples of one another will have graphs with the same intercepts and slope. Select students to share their solutions and methods for finding the intercepts and slope as well as things they notice. While students may notice many things, ensure it is mentioned that in each pair of equations, one is a multiple of the other.
Some questions for discussion:
"How would the graphs of each pair of equations look?" (Each graph would look like a single line since the two equations are equivalent. Time permitting, demonstrate this using graphing technology.)
"Select a pair of equations. Find another equation whose graph would have the same slope and intercepts as the pair already given." (Another multiple of either equation will work.)


correct_option_index: 0