Students draw the height for each triangle based on the given base in this geometry worksheet.

The task in the image is to draw the height for each triangle, given the base. Here's a step-by-step explanation of how to solve this problem:

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What is the "height" of a triangle?

The height (or altitude) of a triangle is a perpendicular line segment drawn from a vertex to the opposite side (the base). The height must be perpendicular to the base.

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Steps to Draw the Height:

1. Identify the Base: Each triangle has a labeled "base." This is the side to which the height will be drawn.
2. Locate the Opposite Vertex: Find the vertex of the triangle that is not on the base. This is the point from which the height will be drawn.
3. Draw a Perpendicular Line: From the opposite vertex, draw a straight line that is perpendicular to the base. This line represents the height of the triangle.
- If the triangle is acute, the height will fall inside the triangle.
- If the triangle is obtuse, the height may extend outside the triangle.
- If the triangle is right-angled, one of the legs can serve as the height if the other leg is the base.

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Solution for Each Triangle:

#### Triangle 1:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 2:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 3:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 4:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 5:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 6:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 7:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 8:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

#### Triangle 9:
- Base: The horizontal side is labeled as the base.
- Opposite Vertex: The top vertex.
- Height: Draw a perpendicular line from the top vertex down to the base.

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Final Answer:

For each triangle, draw a perpendicular line from the vertex opposite the base to the base itself. The exact placement of the height depends on the orientation of the triangle, but it must always be perpendicular to the base.

Boxed Answer:
\[
\boxed{\text{Draw a perpendicular line from the vertex opposite the base to the base for each triangle.}}
\]