Posted by **barb** on Sunday, August 22, 2010 at 9:21pm.

find the slope of the line, if it exists:

coordinates are (-1,-5), (1,-5)

I am doing something wrong because I either get 5 or if I work it another way I get 0

m= either 5 or 0

Which one is it if any?

x1-x2/y1-y2

Can you please help me through this?

- math -
**MathMate**, Sunday, August 22, 2010 at 9:34pm
The slope of a line through two given points P1(x1,y1) and P2(x2,y2) is given by the expression:

m=(y2-y1)/(x2-x1)

Since y2=y1, so y2-y1=0.

Next we have to check if the slope exists:

(x2-x1)=1-(-1)=2 ≠ 0.

Therefore m=0/2=0.

Note: if y2=y1 and x2=x1, then P1 and P2 are two coincident points, and the slope does not exist, because we cannot define a line through two coincident points.

## Answer This Question

## Related Questions

- math - When determining the slope of a line, what is the correct way to leave ...
- slope algebra - given ab and its midpoint m. the coordinates of a are (-10,-3) ...
- Math - On a grid with points R(-2,-6)& S(3,4), what is the slope of line RS? I ...
- algebra - Find the slope of the line through the given points. (2,4) (6,-3). m=...
- Math 116AA - find the slope if it exists of the line containing the pair of ...
- math - find the slope, if it exists, of the line containing the pair of points (...
- math - graph the line with slope 1/2 passing through the point(-5,-2) find the ...
- Algebra - Find the slope of any line perpendicular to the line through the ...
- Math - x=3-3y x+3y=-6 I'm looking for coordinates of where the two lines ...
- My Daughter Stacy needs help in math plz help! - You have to find the x and y ...

More Related Questions