You forgot the absolute values in the perpendicular distance formula
So really, you need to solve , not just
I hope this question goes here.
Heres my question:
The line y-2x+u=0 is 2sqrt5 units from the point (1,-3). Find the possible values of u.
Here is my attempt:
u=15 Or u=?
I hope that makes sense, sorry about the mess I dont know how to use the program here.
I can't find the other answer, but I know that the answer is u=15 or u=-5.