I can't figure out the second half of the question. thanks!

(10 points) Heights (in centimeters) and weights (in kilograms) of 7 supermodels are given below. Height (x) 174 176 176 178 172 178 172 Weight (y) 54 54 55 58 53 57 52 (Note: Compute values to three decimal places of accuracy.) The regression equation is y = 0.779x - 81.79 Regardless of what answer you actually got, suppose your regression equation were y = -80 + 0.8 x. This line predicts the weight of a supermodel who is 171 cm tall to be kg