{XlX is an odd whole number less than 4}

U.S. AIDS Deaths The following scatterplot shows
the cumulative number of reported AIDS deaths.
The data may be modeled x years after 1980 by
f (x) = 2.4 x2 - 14 x + 23, where the output is in
thousands of deaths.
(a) Use f (x) to estimate the cumulative total of
AIDS deaths in 1990. Compare it with the actual
value of 121.6 thousand.
(b) In 1997 the cumulative number of AIDS deaths
was 390 thousand. What estimate does f (x) give?