SOLUTION: Determine whether the graphs of each pair of lines are parallel(PL), perpendicular (PR), or neither (N). 1. y+5=-x x-y= 2 2. y-x= -3 x+4= y 3. 5x-y=8 5y=-x+3

Algebra ->  Graphs -> SOLUTION: Determine whether the graphs of each pair of lines are parallel(PL), perpendicular (PR), or neither (N). 1. y+5=-x x-y= 2 2. y-x= -3 x+4= y 3. 5x-y=8 5y=-x+3       Log On


   

Question 1199013: Determine whether the graphs of each pair of lines are parallel(PL), perpendicular (PR), or neither (N).
1. y+5=-x
x-y= 2
2. y-x= -3
x+4= y
3. 5x-y=8
5y=-x+3
4. 2y=3x+12
3y=2x-5
Answer by math_tutor2020(3816) About Me  (Show Source):
You can put this solution on YOUR website!

I'll do problem 1 to get you started.
Please post one problem at a time in the future.

Solve each equation for y.
y+5 = -x
y = -x+5
Compare this to y = mx+b to find the slope is m = -1 and y-intercept is 5.

Repeat for the other equation
x-y = 2
x = 2+y
x-2 = y
y = x-2
y = 1x-2
This equation has a slope of m = 1

Recap:
y = -x+5 has a slope of -1
y = x-2 has a slope of 1

These two lines are not parallel because the slopes are different.
Parallel lines must have equal slopes.

The lines are perpendicular because their slopes multiply to -1
(slope1)*(slope2) = -1*(1) = -1