How to draw perpendicular and parallel lines with points toolset

picture 1

Assume that we have a triangle ABC and we want to draw the height AH and parallelogram ABCD (draw the red lines on the picture 1).

The following steps show how to do that.

Step 1: Draw line AH ⊥ BC

Select point A. Drag the "add line" tool of the point toolset and drag it to line BC

The small green circles appeared to highlight "meaning points", one of them is a projected point of point A on BC (call it H).

Move the red pointer to H and drop. Point A will be connected with H. (Select AH and use color tool to change color of AH to red)

illustration of step 1

Step 2: Draw AD // BC

Select point A, choose "parallel line" tool of the point toolset (//) and drag it into the area above of BC. Some points will be highlighted as shown in picture 3. Move the pointer to the point 2 and drop it there (see picture 3). Name the new point as D.

picture 3

Connect point C with point D and colour lines AD, CD by red. In the result we have a drawing which is shown in picture 1.

Note: There a variety ways to draw the construction. The above is method by using points toolset, we can also use line toolset, circles toolset or combinations of them.

16.3.2014

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