Question

If l, m, n are three lines such that l // m and n is perpendicular to l, prove that n is perpendicular to m

Answer 1

Provide the figure buddy,Then I can answer to your question,your question is incomplete I think.

Answer 2

Step-by-step explanation:

Given : l, m, n are three lines such that l || m and n ⊥ l.

To prove: n ⊥ m

Proof :  

Since, n ⊥ l

⇒ ∠1 = 90° ………….(1)

Now,  l ‖ m and transversal intersects them.

∠2 = ∠1 ………(2)

Thus, the corresponding angles made by the transversal n with lines l and m are equal.

From eq (1) & (2) , we get ∠2 = ∠1 = 90°

⇒ ∠2  = 90°

Hence, n is perpendicular to m (n ⊥  m).

Figure of this answer is in the attachment below.

Hope this help you !