Question

In the figure, $AB$ is parallel to $CD$, which of the following statements is true?

• A. $a+b={180}^o$
• B. $b+c={180}^o$
• C. $c+d={180}^o$
• D. $a+b+c={360}^o$

Answer 1

Answer: (A)

$a+b={180}^o$

Middle line is parallel to $AB$ as well as $CD$.

Therefore, $a$ and $b$ are consecutive interior angles of parallel line .

Thus $a+b={180}^{\circ }$ parallel lines and their angles properties

So, statement (A) is True.