In RD Sharma Solutions for Class 7 Maths Chapter 17 constructions, students learn how to construct parallel lines. To explain, two given lines are said to be in parallel to each other in a plane if they do not intersect. These lines are supposed to intersect if extended to infinity in both directions. So, when we measure the distance between the two lines, it will be similar throughout the whole length. Parallel lines can be denoted by the symbol "||". If the lines X and Y are parallel to one another, then we can denote their parallel nature using a symbol by X || Y, and it can be read as "X is parallel to Y".
And then, students' study some of the sufficient conditions to create a triangle. Firstly, they obtain knowledge on how side–side (SSS) triangles are formed. In this, the lengths of all three sides are needed to construct the triangle. For example, make an accurate drawing of a triangle with 4 cm, 6 cm, and 7 cm sides. First, draw any line for a base. For example, let's assume a line of 6cm is drawn for the base. Then, with a compass at one end, draw an arc at 5 cm, and with the compass on the other end, draw an at 7cm, cutting the previous arc. Finally, join the endpoints of the base with the point of intersection. As with all the constructions, make sure that the construction lines are not rubbed out. So, this shows that the triangles are constructed accurately.
Likewise, another type is the side–angle–side (SAS) triangle. Here the lengths of two sides and the size of the angle in between are required to construct this triangle. Furthermore, the angle–side–angle (ASA) triangle is another type in which the students construct triangles when the measure of two angles and the length of the side in between are provided. Finally, Right Hand Side (RHS) triangles are made when the hypotenuse and one side of one – angled triangle are similar to the hypotenuse and one side of the other right-angled triangle.