How to draw a triangle? This is taught in the process of studying geometry at school. In order for the task to be completed correctly, it is important to know exactly which triangle to draw: equilateral, isosceles, or inscribed. The rules for drawing these figures will be discussed in this article.
How to draw a triangle with equal sides?
How to draw a triangle whose sides are equal? You can use one of three methods for this.
Such a figure has three sides of equal length, connected by three angles of equal width. It can be difficult to draw a triangle by hand. Therefore, you can use a round object to highlight angles.
Shape options
Be sure to use the ruler and one of the following methods:
- Application of the compass: it is necessary to draw a straight line. Draw a pencil along the straight edge of the paper. This line segment forms one of the sides. And this means that it will be necessary to draw the second and third lines of the same length, each of which reaches a point at an angle of 60 ° from the first line. Make sure there is enough space to draw all three sides!
- Divide the segment with a compass. Insert a pencil and make sure it is sharp! Place the compass point on one end of the segment and place the pencil on the other. Describe the arc. Do not change the set “width” of the tool from the compass point to the point of the pencil. Draw a second arc so that it intersects the first arc that has already been drawn. Mark the point at which the two arcs intersect. This is the top (top point) of the triangle. It should lie in the exact center of the line segment that was drawn. Now you can make two straight lines leading to this point: one from each end of the “lower” line segment. Finish the triangle. Next, using a ruler, draw two more segments of a straight line - these are the sides in the triangle. Connect each end of the original line segment to the point at which the arcs intersect. To finish the job, erase the arcs that you painted so that only the triangle remains.
- Using an object with a round base: this tip is suitable for building an arc. The proposed method is essentially the same as using a compass.
These tips will help you figure out how to draw an equilateral triangle.
Recommendations for the construction of an isosceles triangle
An isosceles triangle is a figure with two equal sides and two equal angles. If you know the length, base and height of the side, this can only be done with a ruler and compass (or just a compass, if dimensions are given).
How to draw an isosceles triangle:
- Given all the lateral lengths. To use this method, it is important to know the length of the base of the triangle and the length of two equal sides.
- Given two equal sides and the angle between them. To use this method, you need to know the length of two equal sides and the measurement of the angle between these two sides.
- Given the base and adjacent angles - you need to know the length of the base, the degrees of two angles adjacent to the base. Remember that two angles adjacent to the base of an isosceles triangle will be equal.
- Base and height. You need to know the length of the base of the triangle, as well as the height of this geometric figure.
Inscribed triangle
How to draw an inscribed triangle? Select a round object. Use an object with a round base. Choosing a CD will be a good option. But you can take another object of the right size. For this method, it is characteristic that the length of each side of an equilateral geometric figure with three angles will be equal to the size of the radius (half diameter) of the circle.
How to draw a triangle if using a cd? Imagine an equilateral triangle that fits into the upper right of the CD. It is necessary to draw the first of the parties. The radius of a circular object is the halfway distance to obtain the desired result. Make sure the lines are drawn evenly.
Using a ruler, simply measure the diameter of the object and draw a line halfway. If not, place a round object on paper, then carefully draw a pencil around the circumference. Remove the object - there should be a perfect circle. Use the straight edge to draw a line through the exact center of the circle: a point that is completely equidistant from any point around the circumference of the circle.
Use a circular object to create an arc. Place the object along the line segment, with the edge of the circle at one end of the line. To ensure accuracy, make sure that the line runs clearly through the center of the circle. Use a pencil to draw an arc - this is a quarter of the way around the circle.
Draw another arc. Now move the round object so that the edge touches the other end of the line segment.
To summarize
The article provided recommendations on how to draw an equilateral triangle, isosceles and inscribed in a circle.