Answer:
a). (-0.04x² + 3x + 49)
b). 79240
Explanation:
a). Population of the pet dogs of a two is given by the expression,
(38 + x - 0.04x²)
And population of the pet dogs of the rest of the towns of the county by (2x + 21).
Where x = Number of years from year 2007
Therefore, total population of the county = (38 + x - 0.04x²) + (2x + 21)
= -0.04x² + (x + 2x) + (38 + 21)
= (-0.04x² + 3x + 49)
b). Difference of years between year 2007 and 2019 = 12 years
Therefore, predicted population in year 2019 = -0.04(12)² + 3(12) + 49
= 36 + 49 - 5.76
= 79.24
Since, population is in thousands,
Therefore, total population of the county = 79.24 × 1000 = 79240