SOLUTION: are the graph of the lines in the pair parallel?explain y=5x+6 -18+3y=-54

Algebra ->  Linear-equations -> SOLUTION: are the graph of the lines in the pair parallel?explain y=5x+6 -18+3y=-54      Log On


   



Question 249105: are the graph of the lines in the pair parallel?explain
y=5x+6
-18+3y=-54

Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
Are the graph of the lines in the pair parallel? Explain.
y=5x+6 ...and... -18+3y=-54

Facts:
1. Two parallel lines share the same slope.
2. To determine a slope, express the equations in this form: y=mx%2Bb
3. m = slope

y=5x%2B6 <--- already in y=mx+b form

-18%2B3y=-54
3y=-54%2B18
3y=-36
y=-36%2F3
y=-12 <--- there is no x value, thus we cannot express it in y=mx+b form

The answer is: they are not parallel because they do not share the same slope.

Here is how the graph of y=5x%2B6 looks like:
graph+%28300%2C+300%2C+-7%2C+7%2C+-7%2C+7%2C+5x%2B6%29

The slope of y=-12 is zero, because it represents a horizontal line in the cartesian plane.
We know that a slope = rise/run... in this case there is no rise and the run goes to infinity (+ and - directions). When zero is divided by any number, the result is zero... thus the slope is zero.
Here is how the graph of y=-12 looks like:
graph+%28300%2C+300%2C+-7%2C+7%2C+-18%2C+7%2C+-12%29