Question

You are asked to "construct" an angle of ${90}^{\circ }$. Which of the following methods is considered appropriate for construction

• A. Using a compass and straightedge, copy an angle that appears to be close to ${90}^{\circ }$ from a diagram in your textbook.
• B. Using a compass and straightedge, construct two parallel lines and label on of the angles ${90}^{\circ }$.
• C. Using a compass and straightedge, construct angles of ${60}^{\circ }$ and ${120}^{\circ }$ and bisect the angle between them.
• D. Using a protractor, draw an angle of ${90}^{\circ }$

Answer 1

The correct option is C Using a compass and straightedge, construct angles of ${60}^{\circ }$ and ${120}^{\circ }$ and bisect the angle between them.

An angle is drawn most appropriate using a compass.

Now bisector of ${60}^{\circ }$ and ${120}^{\circ }$ gives an angle of ${90}^{\circ }$

So option $C$ is correct.

It can also be drawn using protractor but less accurate then compass.