### Lines, 2 Parallel Horizontal

2 parallel horizontal lines with arrows on both ends to show that they extend indefinitely.

### Lines, 2 Parallel Horizontal

2 parallel horizontal lines with arrows on both ends to show that they extend indefinitely. The top…

### Lines, 2 Parallel Slanted

2 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 2 Parallel Slanted

2 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 2 Parallel Vertical

2 parallel vertical lines with arrows on both ends to show that they extend indefinitely.

### 4 Parallel Lines Cut By 2 Transversals

Illustration used to prove the theorem "If three or more parallel lines intercept equal segments on…

### Lines, 3 Parallel Horizontal

3 parallel horizontal lines with arrows on both ends to show that they extend indefinitely.

### Lines, 3 Parallel Slanted

3 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 3 Parallel Slanted

3 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 3 Parallel Vertical

3 parallel vertical lines with arrows on both ends to show that they extend indefinitely.

### Lines, 4 Parallel Horizontal

4 parallel horizontal lines with arrows on both ends to show that they extend indefinitely.

### Lines, 4 Parallel Slanted

4 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 4 Parallel Slanted

4 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 4 Parallel Vertical

4 parallel vertical lines with arrows on both ends to show that they extend indefinitely.

### Lines, 5 Parallel Horizontal

5 parallel horizontal lines with arrows on both ends to show that they extend indefinitely.

### Lines, 5 Parallel Slanted

5 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 5 Parallel Slanted

5 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 5 Parallel Vertical

5 parallel vertical lines with arrows on both ends to show that they extend indefinitely.

### Lines, 6 Parallel Horizontal

6 parallel horizontal lines with arrows on both ends to show that they extend indefinitely.

### Lines, 6 Parallel Slanted

6 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 6 Parallel Slanted

6 parallel lines with arrows on both ends to show that they extend indefinitely. The lines are slanting…

### Lines, 6 Parallel Vertical

6 parallel vertical lines with arrows on both ends to show that they extend indefinitely.

### Construction of a Straight Line Parallel to a Given Straight Line

Illustration of the construction used to create straight line parallel to a given straight line through…

### Cross-Ratio Four Points

The cross-ratio of four points in a line is equal to the cross-ratio of their projections on any other…

### Drawing Parallel Lines Exercise

Parallel lines are drawn by using a triangle in combination with a T-square. To draw a line parallel…

### Drawing Parallel Lines

Using a drawing board and pairs of triangles to draw parallel lines.

### Drawing Parallel Lines Using T-square and Triangle

Parallel lines are drawn by holding the triangle against the T-square at an angle, or another triangle,…

### Straight Line

Equation of a straight line: a) parallel to y-axis, b) parallel to x-axis.

Parallel lines

Parallel lines

Parallel lines

### Parallel Lines

Illustration of parallel lines.

### Parallel Lines Cut by Transversals

Illustration that shows if two parallel lines are cut by three or more transversals that pass through…

### Parallel Lines Cut by Transversals

Illustration that shows if two parallel lines are cut by three or more transversals that pass through…

### Line Joining Midpoints on a Triangle

Illustration used to prove "The line joining the mid-points of two sides of a triangle is parallel to…

### Construction Of A Parallel

An illustration showing the construction used to erect a parallel line. "With C as a center, draw the…

### Positioning

"Observe: That when drawn above the level of the eye, the bottom faces can be seen. (Boxes H, C and…

### Parallel Lines Cut by Parallels, Corresponding Intercepts Proportional

Illustration to show that if parallel lines are cut by any number of parallels, the corresponding intercepts…

### Triangle Divided by Parallel Lines to Form Proportionate Triangles

Illustration to show that if a line is drawn through two sides of a triangle parallel to the third side,…

### Triangle Divided by Parallel Lines to Form Proportionate Triangles

Illustration to show that if a line divides two sides of a triangle proportionally, it is parallel to…

### Rectangle Formed When Two Parallel Lines are Cut by a Transversal

Illustrations to show that if two parallel lines are cut by a transversal, the bisectors of the interior…

### Axes Shift

Any system of coordinate axes to another set which is parallel to the former, but with different origins.

### Line Bisecting Side of a Triangle

Illustration used to prove "The line bisecting one side of a triangle and parallel to another side bisects…

### Sphere With 8-inch Diameter Cut by Planes

An 8-inch sphere cut by parallel planes, one 2 inches from center and the other 6 inches from center.…

### Zones or Segments of Spheres

An illustration of a zone of a sphere. A zone occurs when a sphere is cut by parallel planes that are…

### Zones or Segments of Spheres

An illustration of a zone of a sphere. A zone occurs when a sphere is cut by parallel planes that are…

### T Square

A person using a T square to draw straight lines.

### T Square

A person using a T square to draw triangles.

### Parallel Lines Theorem

Illustration used to prove that "If two straight lines are parallel to a third straight line, they are…

### Parallel Lines Cut By A Transversal Theorem

Illustration used to prove the theorem, "If two straight lines are cut by a transversal making a pair…

### Parallel Lines Cut By A Transversal Theorem

Illustration used to prove the theorem, "If two parallel lines are cut by a transversal, the alternate…

### Line Bisecting Trapezoid Sides

Illustration used to prove the theorem "The line bisecting one of the non parallel sides of a trapezoid…