Question

Given the data points (1, 4), (4, 13), and (6, 19), which of the following equations describes the best-fit line?

A. y = 1 + 3x
B. y = 3 + 1x
C. y = -1 + 3x
D. y = 2 + 3x

Answer 1

plug the points into the lines to see which one all 3 points fits

Answer 2

take two of the points and find the gradient, it will be the same even if you take the third point.
e.g 13-4/4-1 = 3

eliminate all options without a 3x. Now use the point gradient formula: y-y1 = m(x-x1)
so pick any of the three, im picking no 1..
y-4 = 3(x-1)
expand and simplify so y= 1 + 3x

Answer 3

oh i get it i understand. so all i had to do was plug in each and see which on has all the points

Answer 4

yes