Respuesta :

Answer:

a). (-0.04x² + 3x + 49)

b). 79240

Step-by-step 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