Question

Give the equation of the line that is perpendicular to the line y = x + 4 and passes through point (0,-1).

A) y = x - 1
B) y = x + 1
C) y = -x + 1
D) y = -x - 1

So if passes through point o,-1 does that mean that the answer has to be negative? Answer A

Answer 1

Answer A is not correct!
The line y=mx+c that is perpendicular to
y=x+4
has to have the slope equal to the negative of the reciprocal of the given line, i.e. m=-1/(1)=-1
Secondly, since it passes through (x1,y1)=(0,-1), we have
(y-y1)=m(x-x1) where m=-1
(y-(-1))=-1(x-0)
Can you now figure out which is the right one?
Feel free to post your answer for confirmation.

Answer 2

hmm. so I'm assuming it's C then correct!!