Grade 5 math worksheet for naming polygons, featuring various shapes like triangles, squares, and octagons.

Problem: Naming Polygons and Counting Their Sides

The task is to identify the name of each polygon and count the number of lines (sides) in each shape. Below is the solution with explanations for each shape.

---

#### Shape a:
- Name: Triangle
- Number of lines: 3
- Explanation: A triangle is a polygon with 3 sides.

#### Shape b:
- Name: Rectangle
- Number of lines: 4
- Explanation: A rectangle is a quadrilateral (4-sided polygon) with opposite sides equal and all angles being right angles.

#### Shape c:
- Name: Square
- Number of lines: 4
- Explanation: A square is a special type of rectangle where all four sides are equal, and all angles are right angles.

#### Shape d:
- Name: Hexagon
- Number of lines: 6
- Explanation: A hexagon is a polygon with 6 sides.

#### Shape e:
- Name: Octagon
- Number of lines: 8
- Explanation: An octagon is a polygon with 8 sides.

#### Shape f:
- Name: Rhombus
- Number of lines: 4
- Explanation: A rhombus is a quadrilateral with all sides equal in length. It is similar to a diamond shape.

#### Shape g:
- Name: Octagon
- Number of lines: 8
- Explanation: This is another octagon, which has 8 sides.

#### Shape h:
- Name: Pentagon
- Number of lines: 5
- Explanation: A pentagon is a polygon with 5 sides.

---

Final Answer:

\[
\boxed{
\begin{array}{ll}
\text{a. Triangle} & \text{3 lines} \\
\text{b. Rectangle} & \text{4 lines} \\
\text{c. Square} & \text{4 lines} \\
\text{d. Hexagon} & \text{6 lines} \\
\text{e. Octagon} & \text{8 lines} \\
\text{f. Rhombus} & \text{4 lines} \\
\text{g. Octagon} & \text{8 lines} \\
\text{h. Pentagon} & \text{5 lines} \\
\end{array}
}
\]