Learning

Lessons

1. Basics
2. Deductive Reasoning

3 - Parallel lines

4 - Congruent Triangles

5 - Quadrilaterals

6 - Inequalities

7 - Similar Polygon

8 - Rt. Triangles

9 - Circles

10 - Constructions

11 - Areas of 2D objects

12 - Areas and Volumes

13 - Coordinates

Constructions

Objective:

• To be able to make some basic construction.

Lesson 10-1 Construction

Construction is a way to make perfect geometry shapes with only a compass and a straightedge. In this lesson you will need to acquire a compass and a straight edge. Let's start right off by learning how to construct a segment.

Construct: Line

1. Use a straightedge to draw a line. Call it L.

2. Chose any point on the line and label it A

3. Pick a spot on the line with the compass and draw an arc. (using A as the center) Label that intersection on that line 'B'.

To Construct and angle congruent to a given angle

Construct: Angle

1. Draw a ray. Label it Ray RY

2. Using B as center and any radius, draw an arc intersecting segment BA and segment BC. Label the points of intersection D and E, respectively.

3. Using R as center and the same radius as in Step 2, draw an arc intersecting ray RY. Label the arc XS, with S the point where the arc intersects ray RY..

4. using S as center and a radius equals to DE, draw an arc that intersects arc XS at a point Q.

5. Draw Ray RQ.

Now / QRS is congruent to / ABC

To construct the bisector of the angle

Construct: Bisector of an angle

1. using B as center and any radius, draw an arc that intersects ray BA at X and ray BC at Y

2. Using X as center and a suitable radius, draw an arc. Using Y as center and a suitable radius, draw an arc that intersects the arc with center X at point Z.

3. Draw ray BZ

Now ray BZ is bisects to / ABC