Answer:
160
Explanation:
x represents the years since 1990, so at 2030, x = 2030 - 1990 = 40. Replacing this value into the quadratic regression equation, we get:
y = -0.107(40)^2 + 9.008(40) - 28.851 = 160
which is the predicted number of cellular subscriptions per 100 people in Australia in 2030