help please?

Question

a firm wishes to detemine if there is a linear relationship between the number of TV commercials broadcast and the sales of its product.

the data are as follows:

# commercials (x)
12, 7, 9, 15, 6, 15, 10, 4

sales (y)
9, 7, 12, 13, 8, 11, 7, 6

a) find the equation of the least-squares regression line.
b) approximately how many sales would be predict for 20 tv commercials.

Answer 1

a) y = 4.4610 + 0.4784x
b) y(20) = 4.4610 + 0.4784(20) = 14.029 ≈ 14