How would you write an equation in slope-intercept for the line that contains the points (-3,6) & (-1,9)?

Answer 1

Slope = rise over run

rise is change in y, run is change in x

so rise = 9 - 6 = 3
run = -1 - (-3) = 2

therefore slope = 3/2

So using the slope intercept form:

y = mx + b
y = 3/2x + b

we plug in either point to solve for b (the y-intercept):

6 = (3/2)(-3) + b
6 = -9/2 + b
b = 6 + 9/2 = 10.5

y = mx + b where m = 1.5 and b = 10.5

y = 1.5x + 10.5

Answer 2

Find the slope by subtracting y coordinates, 9 - 6 = 3, and x coordinates, -1 - -3 = 2, and making a fraction out of them, since slope is change in y (rise) over change in x (run). So your slope is 3/2, and the basic equation is now

y = (3/2)x + b.

To complete it, fill in the the coordinates of one of the points and solve for b:

6 = (3/2)(-3)+b
6 = -9/2 + b
12/2 = -9/2 + b
21/2 = b

So your equation is y = (3/2)x + 21/2

Answer 3

you need to find the slope...then using slope-intercept use one of the coordinates(plugging in for x and y) and find b( y-intercept)...then put your final answer in slope-intercept form y=mx+b...m=slope, b=y-intercept