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: 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: Problem 1
Based on the definition of each feature of a circle below, label the circle with the appropriate vocabulary words.
Arc:
Part of any curve
Central angle:
An angle formed by two radii with the vertex as the center of the circle
Chord:
A line segment containing two points on a curve
Diameter:
A line segment connecting two points on a curve that passes through the center of the circle
Radius:
A line segment that connects the center of a circle and a point on the circle
Tangent:
A line that intersect a circle at one and only one point
[IMG]
Problem 2
Below is circle
$$A$$
with points
$$E$$
,
$$C$$
,
$$D$$
, and
$$B$$
on the circle.
$$\angle EAC \cong \angle DAB$$
.
[IMG]
What is the relationship between
$$\overline{BD}$$
and
$$\overline {EC}$$
?
Problem 3
Given diameter
$$\overline{CB}$$
, chords
$$\overline{DB}$$
and
$$\overline{CD}$$
, and radii
$$\overline{AC}$$
,
$$\overline{AD}$$
, and
$$\overline{AB}$$
, find the measure of
$$\angle CDB$$
.
[IMG]


aligns: no