The following table gives in years of cars and annual usage if X=36 compute the regression.

X | 40 | 34 | 28 | 30 | 44 | 38 | 31 |

Y | 32 | 39 | 26 | 30 | 38 | 34 | 28 |

**Correct Answer**

Let A = {-18,-9,0,9,18,27}

= {x_{n}|x_{n} = x_{n}_{-1} + 9, x_{1} = -18 & i ≤ n ≤ 6}

or

A = {x|x is a multiple of 9 }

= {9x |x∈ [-2,3]}