Question

Name all the angles formed by the intersection of two lines $AC$ and $BD$ at the point $O$.

• A. $\angle AOB$ or $\angle BOA$
• B. $\angle BOC$ or $\angle COB$
• C. $\angle COD$ or $\angle DOC$
• D. $\angle DOA$ or $\angle AOD$
  

Answer 1

Answer: (A), (B), (C), (D)

$\angle DOA$ or $\angle AOD$


Firstly we will draw a figure of lines $AC$ and $BD$ intersecting at point $O$.


We can observe from the above figure that four angles are formed by intersection of lines $AB$ and $CD$.

An angle is named using the angle symbol $\angle$ and the three points written with the vertex in the middle.

Hence, the four angles formed are:
$\bullet$$\angle AOB$ or $\angle BOA$
$\bullet$$\angle BOC$ or $\angle COB$
$\bullet$$\angle COD$ or $\angle DOC$
$\bullet$$\angle DOA$ or $\angle AOD$