Mathematics for IGCSE & O level - Geometrical Constructions (Section 3 - No. 18)

Which of the following is a key element when constructing a triangle given three sides using a compass?

Using a ruler for all lines.

Ensuring the angles are less than 90 degrees.

Using a pencil that creates a very thick line.

Using only a protractor.

A ruler should be used for drawing straight lines to ensure accuracy.