Question 202128This question is from textbook
: How do I graph this equation by using the slope and y intercept form;5y+3=-5? I don't even know how to start solving it, please help.
This question is from textbook
Answer by PRMath(133)   (Show Source):
You can put this solution on YOUR website! How do I graph this equation by using the slope and y intercept form;5y+3=-5?
Your equation is: 5y + 3 = -5.
I am not sure if you made a typo or not, because I think the equation may really be: 5y + 3x = -5. I think you left off an 'x' here. I'm going to assume that is the case, but at the end, I'll solve this for your equation, just in case you have written it correctly, k?
SO first we're going with the equation that I THINK you intended, which is:
5y + 3x = -5
What you can do is put this equation into the slope intercept form of a line. That equation is: y = mx + b
In the slope intercept form of a line, the "m" refers to your SLOPE and the "b" refers to your Y intercept.
Your equation tho, is not in the slope intercept form of a line. What do we do then? Well, all we have to do is solve for y.
Soooo, take this.....
5y + 3x = -5
5y = -3x - 5 (subtracted 3x from both sides)
This becomes: 
Now your equation is in the y = mx + b format. Do you see that your "m" is
-3/5, and your "b" is your y intercept, which is -1?
Just as additional info:
To find your Y intercept: solve for Y by making "x" = 0
To find your X intercept: solve for X by making "y" = 0
Therefore, in your equation:
you can substitute 0 in for your "X" and you'll get this:
y = -3/5(0) - 1
y = 0 - 1
y = -1
Therefore, when x = 0, your y = -1. Your ordered pair for the y intercept is (0, -1)
To graph this line, use your y intercept as your first point on the graph. Soooo, plot your first point at (0, -1). To find your 2nd point, look at your slope. Remember that your "m" is 3/5 and that is your slope.
Slope is always RISE over RUN, soooo, you look at your first point, which is (0, -1) and you go DOWN (your "rise" was a negative 3, so you had to go down) three points from (0, -1) and RUN over 5 points.
Your second point, then, is located at (5, -4). If you connect the dots between (0, -1) and (5, -4) then you will have your line.
NOWWWWW,if your first equation was written correctly the problem is different. Your first equation was:
5y + 3 = -5
The method is the same. You put the equation in the y = mx + b format by solving for "y". So try this:
5y + 3 = -5
5y = -5 -3 (subtract 3 from both sides)
5y= -8 (-5 -3 = -8)
How do we graph this?
Well, when you have y = to number, you have a HORIZONTAL line and the slope is 0.
When you have X = to any number, you have a VERTICAL line and the slope is undefined.
So, y = -8/5 (or - 1 and 3/5) means that you have a horizontal line that is NEARLY at the -2 spot on the y axis. Just put a dot at -1 and 3/5 and draw a horizontal line at that level.
Your slope will be 0.
I hope this helps. :-)
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