Thread: Finding the slope of a line

We just started doing inequalities in class and I get the basics, but this is what gets me.

M = 7, point (0,-5)

How would I write this in Y = mx + b format?

First, we know m:



Next, we know x and y:



Solve for b:



Notice, if , and is on the line, .

So, now, write your equation down:



Or:

Originally Posted by largebabies

We just started doing inequalities in class and I get the basics, but this is what gets me.

M = 7, point (0,-5)

How would I write this in Y = mx + b format?

The y intercept = -5, therefore

y=7x-5

m=7, (0,-5)


y- (-5)
_______ = 7 : then cross multiply
x-0


y+5= 7x: move five to the other side by subtracting it

so then you get y=7x -5

Thank you all, it's help alot

Although, I need help on another equation, what if there is two points?

example: M = 3/2, point (5,-6)?

First, we know m:



Next, we know x and y:



Solve for b:



So, now, write your equation down:

Thank you once again, although it's supposed to be 27/2 not -27/2

Alright, how about this?

"passes through (4,2) and (0,8)"

Originally Posted by largebabies

Alright, how about this?

"passes through (4,2) and (0,8)"

Find the slope:



From (0, 8) we know the y-intersept = 8.

Use the slope-intercept form of the general equation:

, where m is the slope, and b is the y-intercept.

that helped alot!

although i'm now stuck on another equation , I did the same thing with this and got y= -10/-2 when I needed -5/4.

The equation goes like this.

“passes through (-5,10) and (3,0)”

help?