Question

Which of the following angles can not be constructed using ruler and compass only?

• A. $40°$
• B. $135°$
• C. $120°$
• D. $37.5°$

Answer 1

The correct option is A

$40°$

Explanation for the correct option:

Find the angle which can not be constructed by using a ruler and compass only

It is known that by using a ruler and compass only, we can only draw the angles which are the multiples of angle $15°$.

Here, we can see that angle $40°$ is not a multiple of angle $15°$.

Hence, the correct option is (A).