Question

Construct line $l\parallel$ line $m$, line $l\perp$ line $n$.

Which one of following is true?

• A. $n\parallel m$
• B. $n\perp m$
• C. $l,m,n$ forms a triangle
• D. None

Answer 1

Answer: (B)

$n\perp m$

$\Rightarrow$ Line $l$ $\parallel$ line $m$ [Given]

$\Rightarrow$ Line $l$ $\perp$ line $n$ [Given]

$\Rightarrow$ So, $\angle O={90}^{\circ }$

$\Rightarrow$ Since it's given that line $l$ parallel to line $m$ then,

$\Rightarrow$ $\angle P={90}^{\circ }$

$\Rightarrow$ Hence, line $n$ $\perp$ line $m$