plz neeed help with this If a line passes through the points (-2, -4) and (3, -1), the equation of the line isy+ 4 = 3/5(x+ _____).

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- May 6th 2010, 12:29 PMdaniel323Finding the equation of a line from two given points.
plz neeed help with this If a line passes through the points (-2, -4) and (3, -1), the equation of the line is

*y*+ 4 = 3/5(*x*+ _____). - May 6th 2010, 12:33 PMmohammadfawaz
First find the equation of the line as . You know how do this right?

Now, from which you should be able to factor . - May 6th 2010, 12:40 PMdaniel323
i dont know how to do this so 3/5 is the answer

- May 6th 2010, 12:47 PMundefined
- May 6th 2010, 12:47 PMdaniel323
can u help with this problem also Yfrog Image : yfrog.com/j9math14p

- May 6th 2010, 12:48 PMmohammadfawaz
Ok, first, the equation of the line should be of the form where m is slope and given by .

Hence, . Still need to find b.

the point (-2,-4) belongs to the lines, hence: , therefore: .

Hence, .

So, .

is the answer you need. - May 6th 2010, 12:50 PMdaniel323
i got the first problem already but need second problem

- May 6th 2010, 12:50 PMmohammadfawaz
For the second question, it is clear from the figure that the two lines are parallel. This means that they have the same slope, hence your answer is .

- May 6th 2010, 12:53 PMdaniel323
thank u so much.

- May 6th 2010, 12:54 PMmasters
- May 6th 2010, 12:56 PMundefined
I know the OP said this problem is already solved, but I'd just like to point out that there is an error here, there was a (6/4) where there should have been a (6/5), and the value for b is wrong.

Using point-slope equation, once you verify that the slope is (3/5), you can immediately see that the answer is 2.

Edit: Ah, masters beat me to it. - May 6th 2010, 12:59 PMmohammadfawaz
Oh!

sorry for that!

I had a typing mistake that got me all wrong,

So, 2 is the correct answer