Question

The number of cases of a new disease can be modeled by the quadratic

regression equation y= -2x2 + 40x + 8, where x represents the year.
Which is the best prediction for the number of new cases in year 15?

Answer 1

Answer: 158

Explanation:

A P E X

Answer 2

The number of new cases in year 15 is 158

Solution:

Given that number of cases of a new disease can be modeled by quadratic regression equation:

`y = -2x^2+40x+8`

where x represents the year

"y" is the number of new cases

To find: Number of new cases in year 15

You know that the variable "x" represents the year. Therefore, in order to predict the number of cases in year 15,

Substitute x = 15 in given equation

`y = -2(15)^2+40(15)+8\\\\y = -2 * 225 + 600 + 8\\\\y = -450 + 608\\\\y = 158`

Thus number of new cases in year 15 is 158