few_shots: Example:
Problem/activity:
You’re mixing ingredients for cookies. The recipe says to combine 6 tablespoons, or ¾ stick, of butter with 1 cup of sugar. You accidentally mix in a whole stick of butter (8 tablespoons) with the cup of sugar. How can you fix this?


Standard options: 
A. Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities. For example, “The ratio of wings to beaks in the bird house at the zoo was 2:1, because for every 2 wings there was 1 beak.” “For every vote candidate A received, candidate C received nearly three votes.”
B. Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.
C. Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠0, and use rate language in the context of a ratio relationship. For example, “This recipe has a ratio of 3 cups of flour to 4 cups of sugar, so there is 3/4 cup of flour for each cup of sugar.” “We paid $75 for 15 hamburgers, which is a rate of $5 per hamburger.” (Expectations for unit rates in this grade are limited to non-complex fractions.)


Your response:
B

Now, assign the following problem or activity to one or more relevant standards it aligns with.
shot_info: fl_problem_000972

6
options: Use function notation, evaluate functions for inputs in their domains, and interpret statements that use function notation in terms of a context.

Understand that a function from one set (called the domain) to another set (called the range) assigns to each element of the domain exactly one element of the range. If f is a function and x is an element of its domain, then f(x) denotes the output of f corresponding to the input x. The graph of f is the graph of the equation y = f(x).

Recognize that sequences are functions, sometimes defined recursively, whose domain is a subset of the integers. For example, the Fibonacci sequence is defined recursively by f(0) = f(1) = 1, f(n+1) = f(n) + f(n-1) for n ³ 1.
problem_activity: Activity
The purpose of this activity is to strengthen connections between zeros of a function (input(s) when the output is 0), the output when the input is 0, and the coordinates of the intercept(s) of a graph of the function.
Launch
To ensure that students understand the task before beginning, display one of the functions for all to see, and test an input value that is
not
a zero of the function. For example, evaluate
\(a(\text-5)=\text-5 - 5\)
. Is the output 0? No, the output is -10. So -5 is not an input that would give an output of 0. Draw students’ attention to the list of possible inputs, and tell them that the task is to find the input or inputs for each function that gives an output of 0.
Student Facing
Here are the definitions of some functions, followed by some possible inputs for the functions.
\(a(x)=x - 5\)
\(b(x)=x + 5\)
\(c(x)=x-3\)
\(d(x)=x+1\)
\(f(x)=3x - 6\)
\(g(x)=3x + 6\)
\(h(x)=(x+5)(x+3)\)
\(m(x)=(x+1)(x-3)\)
\(n(x)=(3x-6)(x-5)\)
Possible inputs: -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, and 5.
For each function, decide which input or inputs would give an output of 0.
Here are graphs of
\(b\)
,
\(f\)
, and
\(m\)
. Label each intercept with its coordinates, and be prepared to explain how you know.
[IMG]
Student Response
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Activity Synthesis
Display the correct responses to the first question and ask students to check their work. Invite a student to demonstrate how they know that
\(g(\text-2)=0\)
and
\(m(3)=0\)
(or choose a different function that any students struggled with). The important takeaway is not to look for shortcuts or patterns, but rather understand by evaluating the function why a given number is a zero of the function.
Invite students to share their responses and reasoning to the second question. If not mentioned, emphasize that:
The
\(y\)
-intercept of a graph corresponds to the output when the input is 0, so to find it, evaluate the function when
\(x\)
is 0. For example,
\(b(0)=5\)
, so the coordinates are
\((0,5)\)
of an intercept of the graph.
The
\(x\)
-intercepts correspond to the values found in the first question, the inputs that give an output of 0.
Any time you are dealing with an intercept, one of the coordinates must be 0. The coordinates of an
\(x\)
-intercept are
\((\text{something},0)\)
. The coordinates of a
\(y\)
-intercept are
\((0,\text{something})\)
.


correct_option_index: 0