2x + y= -6, How do you do this problem?

SlowlyFading · 2012-06-25 16:38:09

What's the answer and how did you get it? I would like to understand how to do these problems without help. I just don't get it because I don't know how you do it if there isn't anything put for y.

Bob · 2012-06-25 18:39:22

hi SlowlyFading

That's the equation for another straight line, but written in a different format to your others.

But you haven't said what the question wants you to do with it.

Write in another way? Find some points? Say what the gradient and intercept are?

Bob

SlowlyFading · 2012-06-26 06:16:03

Oh, it wants you to find the points!

anonimnystefy · 2012-06-26 06:27:27

Any specific points? x and y interceptions maybe?

cmowla · 2012-06-26 06:32:55

The easiest way to find two points, especially when the equation is written this way, is to find the x and y intercepts.

[1] We can pretend y is zero to find the x-coordinate of the y intercept (the y-coordinate is zero since we set it to be).

Now we solve for x.

So

is the x-intercept point.

[2] Now we set x equal to zero to find the y-coordinate of the x intercept (the x-coordinate is zero since we set it to be).

So

is the y-intercept point.

Last edited by cmowla (2012-06-26 06:35:55)

Bob · 2012-06-26 06:41:01

hi SlowlyFading

On one of your other posts I did suggest you have a look at the MathsIsFun teaching pages on straight line graphs. Don't know if you did, but I really think it would help. You can experiment with different lines, gradients and intercepts and get some insight into the topic.

Here's two more links that will help:

(i) This will allow you to see the graph if you have y = .............

http://www.mathsisfun.com/data/function … =-8&ymax=8

I've set it up for y = 2x +3 but you can change this to any function of x.

(ii) This version will allow you to input for example 2x + y = -6

You'll have to delete the function that loads up when you go to the page and put the one you want instead.

http://www.mathsisfun.com/data/grapher-equation.html

Give them a try. I'm sure you'll be glad you did.

Bob

SlowlyFading · 2012-06-26 07:25:20

Thanks guys! I understand how you do this type now! I think I do anyway..

anonimnystefy · 2012-06-26 08:03:18

Ok. Post if you need anything else.

Math Is Fun Forum

#1 2012-06-25 16:38:09

2x + y= -6, How do you do this problem?

#2 2012-06-25 18:39:22

Re: 2x + y= -6, How do you do this problem?

#3 2012-06-26 06:16:03

Re: 2x + y= -6, How do you do this problem?

#4 2012-06-26 06:27:27

Re: 2x + y= -6, How do you do this problem?

#5 2012-06-26 06:32:55

Re: 2x + y= -6, How do you do this problem?

#6 2012-06-26 06:41:01

Re: 2x + y= -6, How do you do this problem?

#7 2012-06-26 07:25:20

Re: 2x + y= -6, How do you do this problem?

#8 2012-06-26 08:03:18

Re: 2x + y= -6, How do you do this problem?

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