Originally Posted by

**Coach** Dear forum memebers,

could you please check if my calculations are correct, I have tried several times, I alway keep getting the wrong answer though.

Problem

Find the values for k for which the lines $\displaystyle 2x+ky-11=0$ and $\displaystyle (3-k)x+y+2=0 $are perpendicular.

My solution

$\displaystyle -3x+kx= //frac{k}{2x} $

the bottom numbers have to be the same

so $\displaystyle -3x+kx= 2x $

I always keep getting 5 or 1 as the anwer for k, is it correct?

Thank you in advance!