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


Concept/skill: 
Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

Answer: 
Yes. An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation.

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


Concept/skill: 
Understand that the graph of an equation in two variables is the set of all its solutions plotted in the coordinate plane, often forming a curve (which could be a line).

Answer: 
No. This task does not involve an equation in two variables. There is only 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, assess whether the following problem or activity is 'aligned' with the given Common Core standard in Mathematics.

shot_info: fl_problem_001894_pos_0

HS_0

im_task_000870_neg_0

HS_1

im_task_001160_pos_0

HS_2
standard_description: Understand that a function is a rule that assigns to each input exactly one output. The graph of a function is the set of ordered pairs consisting of an input and the corresponding output. (Function notation is not required in Grade 8.)
problem_activity: Problem 1
Determine the rate of change in each situation. Then describe the relationship using function language (for example, ____ is a function of ____ because _____.)
a.
|  Amt of watermelon in pounds,                                 $$x$$  |   |   |   |   |   |   |
|----------------------------------------------------------------------|---|---|---|---|---|---|
| Cost of watermelon in dollars,                                 $$y$$ |   |   |   |   |   |   |
b.
$${d=25t}$$
, where
$$d$$
is distance in miles and
$$t$$
is time in hours
c.    Giovanni can decorate
$$2$$
cakes,
$$c$$
, every
$$5$$
hours,
$$h$$
.
Problem 2
Determine the starting or initial output value in each situation.
a.
| **                Distance traveled in cab in miles,                *                   $$x$$                  * ** |  0   |  1   |  3   |   4   |
|---------------------------------------------------------------------------------------------------------------------|------|------|------|-------|
|    **                Cost of cab ride in dollars,                *                   $$y$$                  * **    | 2.50 | 4.75 | 9.25 | 11.50 |
b.
| **                Distance traveled in cab in miles,                *                   $$x$$                  * ** |  1   |  2   |   4   |   5   |
|---------------------------------------------------------------------------------------------------------------------|------|------|-------|-------|
|    **                Cost of cab ride in dollars,                *                   $$y$$                  * **    | 4.50 | 7.00 | 12.00 | 14.50 |
c.
$${p=16d+20}$$
where
$$p$$
is the total number of pages read in a book and
$$d$$
is the number of days
Problem 3
The function formula below shows the relationship between temperature in degrees Fahrenheit and degrees Celsius. °F is a function of °C.
$${F=\frac{9}{5}C+32}$$
a.   Determine what 28°C is in °F.
b.   Determine what 23°F is in °C.


aligns: yes