Class 7 · Chapter 10
Practical Geometry
Construction of parallel lines and triangles (SSS, SAS, ASA, RHS).
Read the full chapter
Official NCERT PDF
Full chapter as published by NCERT
NCERT Book Portal
Browse the complete textbook
CBSE Academic Portal
Official CBSE curriculum
Tip: open the NCERT PDF for the original chapter text alongside the notes here.
Detailed theory
Use the property of equal alternate angles. Draw a transversal, mark the given angle at the point on the second line, and use compass to copy.
Key concepts & formulas
01
To draw a line parallel to a given line through a point, use equal alternate angles.
02
SSS construction: use compass with side-lengths as radii.
03
SAS construction: draw the included angle first.
04
ASA construction: draw the included side, then the two angles.
05
RHS construction: draw the right angle, hypotenuse, and one leg.