Answer:
First turn 3x + y = -5 to slope-intercept form (y=mx+b) by subtracting 3x in order to move it to the other side, to get
y = -3x - 5.
So now you have all three lines in proper slope-intercept form. (Don't worry about
y = 7 - 3x, it's still in slope-intercept form, despite the y-intercept and slope being swapped.)
Here are the lines rewritten below.⤵⤵⤵
1. y = -3x - 5
2. y = -3x + 7 or y = 7 - 3x (either way works)
3. y = -3x + 2.5
As we can see, all three lines are parallel.
Because all the slopes are the same and the y-intercepts are different. If the slopes were different, the lines wouldn't be parallel.
I also graphed the lines above, so you can see what I mean.⤴⤴⤴ Hope this helped :)
