standard_description: Recognize a line of symmetry for a two-dimensional figure as a line across the figure such that the figure can be folded along the line into matching parts. Identify line-symmetric figures and draw lines of symmetry.
problem_activity: Task
Consider the algebraic expressions below:
$$ (n + 2)^2 - 4 \qquad \text{and} \qquad n^2 + 4n. $$
Use the figures below to illustrate why the expressions are equivalent:
[IMG]
Find some ways to algebraically verify the same result.


aligns: no