To determine which of the dotted lines is a line of symmetry, we need to check if folding the figure along the dotted line results in both halves perfectly matching each other. A line of symmetry divides a figure into two identical halves that are mirror images of each other.
Let's analyze each option step by step:
Option (a):
- The dotted line is vertical.
- If we fold the figure along this vertical line, the left side does not match the right side. For example, the shaded squares on the left do not align with the shaded squares on the right.
-
Conclusion: This is
not a line of symmetry.
Option (b):
- The dotted line is vertical.
- If we fold the figure along this vertical line, the left side matches the right side perfectly. Every shaded square on the left has a corresponding shaded square on the right.
-
Conclusion: This
is a line of symmetry.
Option (c):
- The dotted line is vertical.
- If we fold the figure along this vertical line, the left side does not match the right side. For example, the shaded squares on the left do not align with the shaded squares on the right.
-
Conclusion: This is
not a line of symmetry.
Option (d):
- The dotted line is horizontal.
- If we fold the figure along this horizontal line, the top half does not match the bottom half. For example, the shaded squares in the top row do not align with the shaded squares in the bottom row.
-
Conclusion: This is
not a line of symmetry.
Option (e):
- The dotted line is vertical.
- If we fold the figure along this vertical line, the left side does not match the right side. For example, the shaded squares on the left do not align with the shaded squares on the right.
-
Conclusion: This is
not a line of symmetry.
Final Answer:
The only figure where the dotted line acts as a line of symmetry is
Option (b).
$$
\boxed{b}
$$
Parent Tip: Review the logic above to help your child master the concept of pattern symmetry worksheet.
