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Each of the eight line segments is perpendicular to 2 line segments. So there are 8 pair in all.
A cuboid has 6 faces, 12 edges and 8 vertices which all meet at right angles.
how many sets of parallel lines are in a triangle
If by two sets of perpendicular lines you mean two pairs of perpendicular lines we can do it. One set of parallel lines is easy so draw that as the first and second lines A right angle from one of them will intersect the other at a right angle so that's the third line and the right angles sorted. The fourth side cannot be parallel to the third so draw it at an angle to the third. We now have two right angles, one set of parallel lines and two pairs of perpendicular lines, first and third, and second and third. What we call it depends on where we are. In the UK it is called a trapezium and in the USA a trapezoid. I'm afraid I don't know naming conventions in other countries.
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A nonagon is a nine-sided polygon. In a nonagon, there are four pairs of parallel lines. This is because the nonagon can be divided into three sets of parallel lines, each containing three parallel lines. Each set of parallel lines consists of three pairs of parallel lines.
4, one set at each corner.
There is only one set of perpendicular lines in a right triangle; the horizontal line and the vertical line that make it 90 degrees.
rhombus
Each of the eight line segments is perpendicular to 2 line segments. So there are 8 pair in all.
Rectangles are made up of 2 sets of parallel lines, which are perpendicular to one another.
The description given could be that of a rectangle.
Well a nonagon is a nine sided polygon. If you make the lines or sides parallel, then you will have a parallel figure. Or some parallel lines on a figure (polygon). If you choose to make your polygon (nonagon) have a pair of congruent sides, then your polygon will have some congruent sides. Therefore it really matters what your shape looks like. For example, a quadrilateral can be a square or a kite (or many others but I'm just using these) a kite might have no parallel lines and a square may have 2 sets of parallel lines. Do you get it? Does that answer your question? FYI: A nonagon is also known as a enneagon :)
A cuboid has 6 faces, 12 edges and 8 vertices which all meet at right angles.
A square has both parallel and perpendicular symmetry. It is composed of two sets of parallel lines that meet at perpendicular angles.
Yes. There are two sets of sides in a square which are parallel to each other and are perpendicular to the other set. Perpendicular means "at 90 degrees to". Hope this helps you.