Question

What is the linear function equation that best fits the data set?

the data set is (1.5,14)(1,12)(2,9)(1.5,8)(3,6)(4.5,4)(4,3)(4.5,0)
yˆ=−43x+9
yˆ=−43x+10
yˆ=3x+15
yˆ=−3x+15
PLEASE HELP

Answer 1

D. y = -3x + 15

Explanation:

I just took the test!!!

Answer 2

To form an equation for a straight line, we need the value of gradient and the y-intercept

The formula to find gradient is
`(S_(xy) )/( S_(xx) )`


`S_(xy)=`∑
`(xy)- ((∑x)(∑y))/(n)`

`S_(xy)= 111- ((22)(56))/(8)`

`S_(xy)= (1232)/(8)=-43`


`S_(xx)=`∑
`x^(2) - (∑x)/(n)`

`S_(xx)=75- \frac{22^(2)} {8}`

`S_(xx)=14.5`


`m= (S_(xy))/(S_(xx))`

`m= (-43)/(14.5)=-2.9`≈-3

where m is the gradient

to find c (y-intercept)

`c=mean of y-(m)(mean of x)= (56)/(8) -(-3)( (22)/(8))=15.25`≈15

Hence the equation of the straight line is
`y=-3x+15`