what is the slope of the line that passes through the pair of points
(-6,-1), (0,-9)
i need help .!!

Question

what is the slope of the line that passes through the pair of points 
(-6,-1), (0,-9) 
i need help .!!

amistre64 · Answer

would you be able to tell the slope of a line that passes thru the origin and a given point (a,b)?

amistre64 · Answer

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amistre64 · Answer

if so, then i would suggest moving these points so that one of them is at the origin ...

anonymous · Answer

ok

amistre64 · Answer

do you agree that moving points, does not change the slope between them?

what we do to one point, we do to the other

(-6,-1)    (0,-9) 
     +9          +9
------    ------
 (-6, 8)      (0 , 0)

amistre64 · Answer

now we simply can read the slope off the nonzeroed point.  -8/6  and reduce

amistre64 · Answer

in general,   if we have to point (xo,yo)  and (x1,y1)

(xo,yo)         (x1,y1)
-xo-yo       -xo -yo
-----         -------
  0,0         x1-xo , y1-yo

slope between them is

y1-yo
----- ;   which is exactly how the slope formula is defined
x1-xo