2. POINTS
• We may think of a point as a “dot” on a
piece of paper.
• We identify this point with a number or a
CAPITAL letter.
• A point has no length or width, it just
specifies an exact location.
4. LINES
• STRAIGHT LINES don’t have a begginig or an
end.
• RAYS has a beginning point but it hasn’t an
end point.
• LINE SEGMENT has a beginning point and an
end point.
• CURVE LINES
• POLYGONAL LINES
• PARALLEL LINES
• SECANT STRAIGHT LINES
• PERPENDICULAR LINES
6. ANGLES
• Two rays that share the same endpoint,
called vertex.
• Clasification by measurement:
– Acute<90º
– Right =90º
– Obtuse>90º
– Flat =180º
– Full =360º
• We use the protactor.
7. ANGLES
• ANGLE BISECTOR is a ray that divides an angle into two
equal angles.
– Place the compasses' point on the angle's vertex.
– Adjust the compasses to a medium wide setting. The exact width
is not important.
– Without changing the compasses' width, draw an arc across
each leg of the angle.
– Place the compasses on the point where one arc crosses a leg
and draw an arc in the interior of the angle.
– Without changing the compasses setting repeat for the other leg
so that the two arcs cross.
– Using a straightedge or ruler, draw a line from the vertex to the
point where the arcs cross
How to make it
8. ACTIVITY 3 and 4
• Use the protactor and clasify the angles.
• Draw angles.
• Draw the angle bisector.
9. POLYGONS
• A polygon is a closed figure made by
joining line segments.
• Polygons can be regular or irregular; o, .
– Triangles (3 sides)
– Quadrilateral (4 sides)
– Pentagon (5 sides)
– Hexagon (6 sides)
– Heptagon (7 sides)
– …
11. CIRCLE
• Radius: it’s the distance from the center
of the circle to the outside edge.
• Diameter: it’s the longest distance
across a circle.
• Circumference: it’s the perimeter, the
distance around the outer edge.
• Chord: it’s a line segment that connects
one point on the edge of the circle with
another point on the circle.
• Arc: it’s a segment of the circumference
of the circle.
• Sector: it’s a pie shaped portion of the
área of the circle.
12. ACTIVITY
• Draw a circle using the compass (12 cm of
diameter)
• Write the parts of the circle and the
circumference.
• Calculate the circumference 2xπxr2