00:01
Okay, for these problems, we're given a formula to follow.
00:06
It's nb plus sigma x, which is our sum of the x values times a equals the sum of the y values.
00:17
The second equation we have is the sum of the x values again times b again, plus the sum of the x values squared times a.
00:28
And that's going to equal the sum of the product of the x and y values.
00:35
So maybe this is saving you some time, but i took the time to add all these things up.
00:39
So in the number of things we have, the number of points, is eight.
00:44
If we add up all of our x values, it's going to give us 36.
00:50
If we add up all of our y values, we're going to get 30 .3.
00:58
If we add up all of the squares of our x values, it's going to give us 204.
01:07
And if we add up all of the product of our x and y values, that's going to give us 179 .4.
01:17
So now we just need to solve this system of equation.
01:20
So i'll do that on the next slide.
01:23
Okay, so we're going to have 8b plus 36a is equal to 30 .3.
01:40
Okay.
01:40
And then our second equation, we're going to have 36b, some of the xes again, plus 204a, and that's equal to 179 .4.
01:59
Okay, so we're going to use the process of elimination on these.
02:03
I notice that my b values, i can make the both into 72 to have equal coefficients.
02:13
So, then multiply my top equation by 9 and my bottom equation by 2.
02:19
Okay, so that's going to be 72b as our equivalent equation.
02:26
9 times 36 is 324.
02:33
9 times 30 .3 is 272 .7.
02:41
Okay, our second equation, there's our 72b again.
02:47
This is going to be 408, 408, and then 358 .8...