How do you write the equation of a line in point slope form and slope intercept form given points (-3, -4) (3, -2)?

1 Answer
May 7, 2015

Since both requested forms require the slope, let's start there:

#m= (Delta y)/(Delta x)#

# = ((-2)-(-4))/(3-(-3))#

#=2/6 = 1/3#

The general point slope form is
#(y-y-1) = m(x-x_1)#
or, in our example,
#y-(-4) = 1/3(x-(-3))#

With a little rearranging we can convert this into the slope intercept form (which in general is #y=mx+b# with a y-intercept at #b#)

#y+4 = 1/3(x+3)#

#y+4 = 1/3x +1#

#y= 1/3x -3#