Question

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

Answer 1

Answer:

because answer is yes because it is simply to say that the line l is parallel to M line and n is perpendicular to l so line n and perpendicular to a line m

Answer 2

let the gradient of lines l,m,n be

m_{l},m_{m},m_{n}

then, according to question,

m_{l}=m_{m}

and

m_{n}m_{l}=-1

so,

m_{n}m_{m}=-1

so n is perpendicular to m