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

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


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.

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
standard_description: Understand solving an equation or inequality as a process of answering a question: which values from a specified set, if any, make the equation or inequality true? Use substitution to determine whether a given number in a specified set makes an equation or inequality true.
problem_activity: Problem 1
The perimeter of a rectangle is 54 cm. If the length is 2 cm more than a number and the width is 5 cm less than twice the same number, what are the dimensions of the rectangle?
Problem 2
A plot of land for sale has a width of
$$x$$
feet and a length that is 8 feet less than its width. A farmer will only purchase the land if it measures 240 square feet. What value for
$$x$$
will cause the farmer to purchase the land?


aligns: no