This document defines different types of angles such as acute, obtuse, right, and perpendicular. It also defines parallel lines as lines that are always the same distance apart and perpendicular lines as lines that intersect at right angles. Some examples of perpendicular lines given are floor tiles and table corners, while parallel lines examples include opposite sides of an eraser and ruler.

1. PARALLEL AND
PERPENDICULAR
PREPARED BY: GERALDINE S. CACHERO
MATHEMATICS 5

2. REVIEW: ANGLES
• An angle is a union of two non-collinear rays with common
endpoint. The two non-collinear rays are the sides of the angle
while the common endpoint is the vertex.
ray
verte
x
ray

3. ACUTE ANGLE
• An acute angle measures more than 0° but less than 90°.
>𝟎° but
<𝟗𝟎°

4. OBTUSE ANGLE
• An obtuse angle measures more than 90° but less than 180°.
>𝟗𝟎° but
<𝟏𝟖𝟎°

5. RIGHT ANGLE
• A right angle measures exactly 90°.
𝟗𝟎°

6. ACTIVITY
Identify the following angles:
1. 2.
3.

7. PERPENDICULAR
• lines that intersect (cross) each other at right angles
𝟗𝟎°
Examples: floor tiles, corners of tables and corners of the
windows

8. PARALLEL
• lines that are always the same distance apart
Examples: opposite sides of an eraser and opposite sides of a
ruler