Question 74425: heyy.
okay
so i need help again.
heres the question..
Write an equation of the line through (-1, -2) and (-1, 1).
First, use the two points to find the slope.
HELP ME!!
hahaha
please!
Answer by josmiceli(19441)   (Show Source):
You can put this solution on YOUR website! Given any 2 points, you can draw a line through them, and
that line will have a certain slope.
What's the definition of slope?
It is slope = (change in y) / (change in x) or
slope = (change in vertical) / )change in horizontal) same thing
So how do you find these?
When you're given 2 points, you can call them  and 
Then you can say = ( , )
and also can say = ( , )
The change in y is -
The change in x is -
Now just plug in the numbers in the problem
= ( , )
= (, )
Change in y = -
change in x = -
slope = (change in y) / (change in x)
slope = 
slope = 
What does this tell you? First, dividing by 0 is not allowed, but
the 0 tells you that there is no change in x since you're
subtracting -1 from -1.
No change in x means the line is vertical.
If there were no change in y, the line would be horizontal
The slope of a vertical line is infinity
Pick any point on this line. x will be -1 no matter what
y is. So, the equation of the line is 
|
|
|
