Question

In the figure, $CD$ and $EF$ are perpendicular to a line $AB$. Verify that $CD$ is parallel to $EF$.

Answer 1

The interior angle made by $CD$ and $EF$ with $AB$ will be ${90}^0$ which tells which if added makes ${180}^0$.

By interior angle theorem,

Both lines must be parallel with each other.

Hence, this is this answer.