SOLUTION: solve the system by graphing x+y=3 x+y= -1 My question is do I just pick a number to plug in for x & y or do I use the 3 and 1 somehow?

Algebra ->  Graphs -> SOLUTION: solve the system by graphing x+y=3 x+y= -1 My question is do I just pick a number to plug in for x & y or do I use the 3 and 1 somehow?      Log On


   



Question 109888: solve the system by graphing
x+y=3
x+y= -1

My question is do I just pick a number to plug in for x & y or do I use the 3 and 1 somehow?

Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=3 [re-write in the slope-intercept form: y=mx+b]
y=-x+3
SLope = m = -1
y-intercept = 3 at point (0, 3)
and
x+y=-1
x+y=-x-1
Slope=m=-1
y=intercept = (-1) or (0, -1)
.
Since the slopes are equal, the lines will be parallel.
.
Graphing using the y-intercept and counting up or down; left or right for the slope gives:
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+-x%2B3%2C+-x-1%29+