You are not logged in.
Hello everybody,
I need the answers to 5 problems and how exactly you got that answer using the elimination method. I want to understand how to do these!
The Questions:
10. y = (2/3)x - 1
y = -x + 4
11. x + y = 0
3x + y = -4
12. 4x + 3y = -15
y = x + 2
13. x + 2y = -4
4y = 3x + 12
14. y = 2x
x + y = 3
Thanks! <3
Okay BobbyM, thanks a lot for all the help!
I'm sure I got annoying at times and as you can see math isn't my strong-point, nonetheless thanks!
Cool, thank you! One last question, "If this trend continues, what will Sam's bill be in July?"
So, I need to change
(x1, y1) = (1, 115)
(x2, y2) = (5, 83)
to
(x1, y1) = (1, 115)
(x2, y2) = (7, 83)
And then do the same thing?
It was an accident, it's supposed to be there. (y - 115) = -8 (x - 1)
(y - 115) = 8 (x - 1)
y -k = -8(x - h)
y -k = 8(x - h)
It reduces down to -0.125 I believe.
Okay, so then it's:
(x1, y1) = (1, 115)
(x2, y2) = (5, 83)
But then that's only (x1, x2) not (x1, x2) and (y1, y2)?
I thought we had to break 1,115 into two points? And the same with 5,83
(x1, x2,) = (1, 115)
(y1, y2) = (5, 83)
How's that?
This is the formula my lesson uses:
Example 1: Find the equation of the line through the points (2, -1), (-4, 3)
First, find the slope as we did in lesson 11.
(y2 - y1)
(x2 - x1)
(3 - -1)
(-4 - 2)
(4)
(-6)
So our slope is -2/3
Next, pick one of the points (either one will do) to put into the equation y -k = m(x - h). Be sure to change the signs of the coordinates.
y + 1 = -2/3(x - 2
The y2 83 from the second set of coordinates.
Yes I understand where the y1 went, at least i think I do. You put it in so you could subtract it from the 83 right?
That's the formula I used. I subtracted 83 - 115 and got -32, and subtracted 5 - 1 and got -2.
So the point-slope form is y + 115 = -32/-2(x - 1) I believe.
Won't I also need to use the other set of coordinates as well? (x2, y2) = (5, 83)
y1 would be the second number in the coordinates so also 1?
x1 is 1?