Question

How do you find an equation of the line that passes through the point and has the indicated slope m? (2,4); m = -1

With this one, isn't the formula y-y1=m(x-x1)

Answer 1

thats as good as any other form of the equation of a line

Answer 2

Okay, but when I figure it, I can't seem to get it to come out to what you got

Answer 3

Is (2, 4) = 2 = x1 and 4 = y1?

Answer 4

-1 would = m correct?

Answer 5

y-4 = -1(x-2) ; do you wanna shift it to the slope intercept now?

Answer 6

Okay, I switched the y-4 and had -4-y, and just input 0
That is where my mistake was then...So you can have many different equations then for these types of problems?

Answer 7

I just have to show an equation at this point...

Answer 8

yes; you can have as many equations as there are ways to move everything around. All the forms of the equations do is move stuff without changing any values

Answer 9

Wow, and I noticed that y-4=-1(x-2) cannot be simplified; therefore will be an equation correct?

Answer 10

its like having a box of crayons; it doesnt matter how you arrange them in the box; you still have the same box of crayons

Answer 11

Nice... Your always such a good help.

Answer 12

How is the family?

Answer 13

yes, the point slope form that is there is a valid form of a line equation :)

Answer 14

You helped me before, personally. JaniSmit...remember

Answer 15

if its been longer than 3 days, its merged into the past memories lol

Answer 16

family is ok; daughter decided to sprain her ankle tho

Answer 17

Nice...poor little thing...hope she recovers quickly

Answer 18

:) yeah, shes bound to break other parts tho

Answer 19

I told you my husband is military and I'm helping him with his math classes...this is the last one..thank God

Answer 20

So when I have to find an equation of the line that passes through the given points such as (2,1) and (2,5) I would use the same formula right?

Answer 21

slope formula; which is just telling you to subtract one point from another

Answer 22

Or, m=y2-y/x2-x1

Answer 23

Gotcha...awesome...i caught that one ..woohoo..

Answer 24

yeah, that one...

(x , y )
-(x1 , y1)
---------
(x-x1, y-y1)

Answer 25

Okay, so with (2,1) and (2,5) I would do...
m= 5 -1 / 2 - 2 = 4 / 0 = 4?????

Answer 26

(2,5)
-(2,1)
------
0,4; slope = y/x = 4/0

The ONLYtime you get this is when you have a vertical line.

Answer 27

when you have a vertical line then the equation is simply:

x = whatever your x value was in your points

Answer 28

So it equals 0 then? As if a fraction 4/0=0

Answer 29

not zero; undefined

Answer 30

Undefined when x1=x2............

Answer 31

0 slope is like driving on a flat road; its just flat, no elevation changes

Answer 32

4/0 is like jumping off a cliff; you only go in one direction

Answer 33

That slope could be going in any direction correct? Up and down or sideways right..

Answer 34

Funny, I got you exactly..i understand

Answer 35

I have another tough one that i'm lost with ..you game?

Answer 36

sure :)

Answer 37

This one says to find an equation of the line that has slope m and y-intercept be? for the equation m = -2; b= -1

I am unsure which formula to use really..

Answer 38

Maybe the y-y1=m(x-x1)

Answer 39

the one thats called slope intercept form :) since it gives a slope and an intercept

Answer 40

y = mx +b

Answer 41

y = -2x -1

Answer 42

Darnit, you beat me..I found some formulas just now....it said exactly what you said..your awesome

Answer 43

yeah :)

Answer 44

Wow, so these are literally just chosing equations that do not need to be solved..

Answer 45

well, the solution IS the line that is created by them

Answer 46

which is why they are called 'line' equations :)

Answer 47

one solution is called a point; all solutions are called a line

Answer 48

So, If I am trying to find 2 different slopes that are parallel to one another, do I just create 2 different equations?

Answer 49

I do not recall this kind of formula

Answer 50

yep; but they should have the same slopes

Answer 51

ax+by = c

ax + by = d are parallel lines

Answer 52

when c=d they are the same line

Answer 53

Basically, if i had to find an equation for (-1,3) that is parallel to the line passing through points (-2, -3) and (2,5), would that formula fit that description?

Answer 54

perpendicular lines are:

ax + by = c

bx - ay = d

Answer 55

you are given a point; and some slope information; use slope point form after using the slope formula to determine the slope

Answer 56

Okay, I see one formula in my book that says "General Form" Ax + By + C = 0

Answer 57

yep; that is a general form

Answer 58

Wow, this one is actually confusing me..darnit..i'm really getting it too

Answer 59

(-2, -3)
-( 2 , 5 )
---------
-4, -8; slope = y/x = -8/-4 = 2

Answer 60

lol ..... i messed that one up

Answer 61

Wow, i'm lost..ugh

Answer 62

y-3=2(x+1)

Answer 63

Okay, so point-slope formula first

Answer 64

slope formula first; cant plug in a slope unless you get a slope first

Answer 65

Okay, just to verify....y=mx+b (point slope comes first)

Answer 66

Then, the Actual slope-intercept form? y=mx+b?

Answer 67

Okay, so y-3=2(x+1) is the actual point slope formula....and y=mx+b is the slope-intercept form

Answer 68

yep;

slope formula, then

point slope, then

slope intercept

Answer 69

y - 2x +2 +3

y = 2x +5

Answer 70

I guess that is where i'm getting confused..I am using the (-2, -3) and (2, 5) for this formula right?

Answer 71

The second part assuming...i'm actually lost here

Answer 72

Hey, I know you are busy and you have been an enormous help. Thank you so very much. I appreciate all your hard work. Makes so much more sense now.