SOLUTION: What if I have x-y=-3 I dont understand

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Question 801572: What if I have x-y=-3
I dont understand
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

if you have x-y=-3, means you have an equation of a line
you can solve it for y
x-y=-3.....add y to both sides
x-y%2By=y-3

x-cross%28y%29%2Bcross%28y%29=y-3

x+=y-3....add 3 to both sides
x%2B3+=y-3%2B3
x%2B3+=y-cross%283%29%2Bcross%283%29
x%2B3+=y+
or y=x%2B3+.....this is equation of a line in slope-intercept form y=mx%2Bb where m=slope and b=y-intercept
in your case m=1 and b=3
so, your line has positive slope, means goes through I and III quadrant
it also crosses y-axis at point (0,3)
we need one more point to graph it:
let's find x intercept if y=0
0=x%2B3+
-3=x++
so, x intercept is at (-3,0)

see it on a graph:

+graph%28+600%2C600%2C+-10%2C+10%2C+-10%2C+10%2C+x%2B3%29+