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proof of y2-y1/x2-x1

I know you use this formula to work out the gradient.
(5 , 7) (6, 8)
Here you would do (8-7)/(6-8) to get a 1/2 as the gradient, but i don't understand how this formula gets me the answer? If you are a good mathematician help me please, I really want to understand what I'm doing rather than just doing it for no reason.
Original post by AngryFish
I know you use this formula to work out the gradient.
(5 , 7) (6, 8)
Here you would do (8-7)/(6-8) to get a 1/2 as the gradient, but i don't understand how this formula gets me the answer? If you are a good mathematician help me please, I really want to understand what I'm doing rather than just doing it for no reason.


The gradient of a straight line is the change in the y-value per change in x by 1. Dividing the change in y by the change in x gives you this value.
Original post by AngryFish
I know you use this formula to work out the gradient.
(5 , 7) (6, 8)
Here you would do (8-7)/(6-8) to get a 1/2 as the gradient, but i don't understand how this formula gets me the answer? If you are a good mathematician help me please, I really want to understand what I'm doing rather than just doing it for no reason.


i feel that like that is the actual(one of many) definitions of the gradient

i mean if you want to see for yourself i guess you could look at the graph but then when you think gradient you'll think the slope of the line(when you connect 2 points) is the gradient. Working it out is essentially simple.

https://www.mathsisfun.com/definitions/gradient.html
This one says that the gradient is how steep a line is so ye...
Reply 3
Original post by AHappyStudent
The gradient of a straight line is the change in the y-value per change in x by 1. Dividing the change in y by the change in x gives you this value.


thx
(edited 6 years ago)
Reply 4
Original post by will'o'wisp2
i feel that like that is the actual(one of many) definitions of the gradient

i mean if you want to see for yourself i guess you could look at the graph but then when you think gradient you'll think the slope of the line(when you connect 2 points) is the gradient. Working it out is essentially simple.

https://www.mathsisfun.com/definitions/gradient.html
This one says that the gradient is how steep a line is so ye...


yee i know how to calculate gradient (steepness), i just wanted the proof, or understanding of how you would use (y2-y1)/(x2-x1) to calculate it.
Its change in y over change in x.
Original post by AngryFish
yee i know how to calculate gradient (steepness), i just wanted the proof, or understanding of how you would use (y2-y1)/(x2-x1) to calculate it.
Its change in y over change in x.


o rite xD

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