Thread: Finding the zeros and intercepts---help / check answer?

Originally Posted by 11rdc11

$\displaystyle 2x - 3y = C $

$\displaystyle -3y = -2x + C$

$\displaystyle y = \frac{2x}{3} -\frac{C}{3}$

Ok now put in whatever value for C

The only thing that is happening is the graph is moving up or down. It is easier to see what I'm trying to explain. Try plooting it and you will see what I mean.

Sorry, I took a break and did another section of math which I've completed for the most part.
Okay, I am still stuck on this question.
Let's plug in "2" for C...how would I proceed in solving it? I cannot add 2x + 2 together...I'm really trying to remember how to do this...
and how would I plot it?
Thanks in advance.

What are you trying to solve for?

Wait...I'm not sure. Am I solving for anything? I think I need to solve for x and y if I want to plot the correct corresponding lines to the number I put in for C?
Ahh I'm so confused...

If you put in 2 for C you have

$\displaystyle y = \frac{2x}{3} -\frac{2}{3}$

Are they asking you to find the x and y intercepts of this equation? Thats the only thing I can see the problem is asking to solve for?

I guess so?

If C is an arbitrary real constant, an equation such as 2x - 3y = C is said to define a family of lines. Choose four different values of C and plot the corresponding lines on the same coordinate axes. What is true about hte lines that are members of this family?

Do you need the intercepts to plot those lines? If you do I am not sure how to solve them. Thanks again.

It would help. Plot them and the answer will be obvious