few_shots: 
Example 1:
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.

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


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:
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).

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


Answer: 
No. This task does not involve an equation in two variables. There is only one variable, x.

Example 3:
Concept/skill: 
Construct a tangent line from a point outside a given circle to the circle.

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 $P$.


Answer: 
No. This task does not involve drawing lines that are tangent to circles. The only line that may be drawn is the ray between points P and B.

Now, assess whether the following problem or activity is 'aligned' with the given Common Core standard in Mathematics.

shot_info: fl_problem_001894_neg_0

HS_0

im_task_000870_neg_0

HS_1

im_task_001160_neg_0

HS_2
standard_description: Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers.
problem_activity: Problem 1
Mr. Wynn now wants to cover a part of the gym with butcher paper to work on a large painting. He covers a section of the gym that is 30 feet long and 35 feet wide. Then he realizes he needs a bit more space for the painting and adds a section of butcher paper that is 4 feet long and 35 feet wide.
a.   How many square feet of butcher paper did Mr. Wynn use for his painting?
b.   What is the total length and width of Mr. Wynn’s painting?
Problem 2
a.   Label the area model to represent 31 × 23 and to find that product.
Decompose each number into its base-ten units (tens and ones) and write them in the boxes on each side of the rectangle.
[IMG]
Label regions A, B, C, and D with their areas. Show your reasoning.
Find the product that the area model represents. Show your reasoning.
b.   Here is one way to calculate 31 × 23. Each number with a box gives the area of one region in the area model.
[IMG]
In the boxes next to each number, write the letter of the corresponding region.
There is a 1 above the hundreds digit in the sum. What does that 1 represent?
Problem 3
Estimate each product. Then use any method to solve.
a.
$$26\times37$$
b.
$$81\times52$$
c.
$$68\times73$$


aligns: no