Question

what is slope intercept form? i mean when they are wanting me to express it in slope intercept form from looking at a graph is that different than saying (3,-4)?

Answer 1

Slope intercept form is the form of y=mx + b where the slope is m, and the y-intercept is b. Slope can be calculated as follows:
\[m=\frac{ y _{2}-y _{1}}{ x _{2}-x _{1} }\]The y-intercept is the point in which the graph hits the vertical axis of the y-axis. So that means if you have a y-intercept at point b, then it is located at point (0,b) for whatever value b is.

Answer 2

so if on my graph the x axis is marked at -4 and the y axis is marked at 1 how would i write that out then

Answer 3

when you get time
http://www.khanacademy.org/math/algebra/linear-equations-and-inequalitie/v/linear-equations-in-slope-intercept-form

Answer 4

Ah, well then they give you two points, so you are able to find the point. The graph on the x-axis is marked at -4, so that's an x-intercept, which can be written as the following point (-4,0). Same with the y-axis, which is marked at 1 as a y-intercept, written as (0,1). So just calculate the slope, then put it in the y=mx+b form.

Answer 5

so would it be y=-4x+1???

Answer 6

I think you did the slope upside down

Answer 7

I believe that you have it reversed. The top is the Y values, and the bottom is the X values, when calculating the slope.

Answer 8

what lol

Answer 9

so it is y=1x+-4

Answer 10

the y-intercept is 1 (your first equation)

Answer 11

Try calculating the slope using the actual slope formula I provided earlier.

Answer 12

the slope is the difference between the y values divided by difference of x values

Answer 13

im confused ugh

Answer 14

your 2 pts are (-4,0) and (0,1)

Answer 15

correct

Answer 16

the 2nd number is the y

Answer 17

yeah

Answer 18

(-4,1)

Answer 19

so 0-1 is the y difference
-4 -0 is the x difference

Answer 20

you divide to get a singe fraction -1/-4 = 1/4

Answer 21

oh ok that makes more sense

Answer 22

y= (1/4)x +1

if x is 0 you get y= (1/4)*0+1 and y=0+1=1
so (0,1) is on the line

if x= -4
y= (1/4)*-4 +1 = -4/4 + 1 = -1+1 =0
so
(-4,0) is on the line
looks good

Answer 23

awesome thx