Algebra help? Anyone? PLEASE?

Question

Okay so I am doing slope and y-intercepts and x-intercepts and all that jazz.
But I am having a problem finding the slope when given two points on the line.
I know the formula is this:
M = Y2 + Y1
_______________
X2 + X1

and yet I can't seem to figure it out.

Here are the questions I am having difficulty with:

A line which contains these points: (-3,3) &
(-8,-2) would have a slope of _________?
&
What is the slope of a line that with the points (2,4) and (4,-2)?

I am leaving today so I really need to get this done within the next hour or so...
So your help is GREATLY appreciated! Thank you SO much!

PS--when you give your answer can you please explain how you came up with it? Thanks!

Answer 1

Whee! Linear equations! I remember those! Lucky you, you don't have to deal with binomials.
Okay. Let's begin.
3 as y is 5 greater than -2 as y. -3 as x is 5 greater thant -8 as y. So easy. The slope is 1. As the x values increase, the y values increase by the same.
On to the next one.
4 as y is 6 greater than -2 as y. 2 as x is 2 less than 4 as x. The slope is -3. As x increases, y decreases by three.
It's simple. The formula for slope is:
(2nd y-1st y)/(2nd x-1st x).
The second y first y doesn't really matter, the only thing that matters is that the order of the y's is the same in the x's. So don't put 1st y in the beginning of the first half and the 2nd x in the beginning of the second half. Keep it the same.
Good luck with algebra!

Answer 2

In your first equation, M is the slope.

Therefore, Slope = 3+ (-2)
____________
(-3)+ (-8)

The slope would be 1/11

You would do the same equation for the 2nd amount of points.

Slope = 4+(-2)
_______
2+4

The slope would be 1/3.

I hope this helps!

Cheers!

Answer 3

Do your own homework and pay attention in class. This stuff is easy. And the formula is Y=MX+B You don't have enough info for the first 2.