Question

Which of the following is an equation of a line perpendicular to y=x-1.
Possible answers listed below:
A. 2y-3=x
B. y=-x+3
C. y=x-3
D. y+3=x

Answer 1

the answer would be B.

Answer 2

May you please explain?

Answer 3

of course :)

Answer 4

ok...so perpendicular means the opposite reciprocal of something. in the equation your slope is 1/1 which is just one. now we need the opposite reciprocal of 1 which is -1. now for future problems...say you have a slope of 4/3 and you need a slope perpendicular to that you would flip the fraction to 3/4 which is the reciprocal and now to make it opposite you put a negative in front being -3/4 ....i just wanted to give another example of opposite reciprocal so you understand how it works. Now that we found out the opposite reciprocal of the slope from your equation is -1 now you know that the equation will look like y= -x plus or minus the y-intercept. when you look at your choices and put all the equations in standard which is y=mx+b you will find all the slopes are positive which cant be perpendicular to y=x-1 except for B. B is the the right answer. does that make sense? :)

Answer 5

Yes, so the slope is the only thing that matters when it comes to finding the perpendicular line to an already given equation?

Answer 6

yes you are correct :) you can always send me a question and i can try and help in the future :)