Question

according to a census, there were 66 people per square mile (population density) in a certain country in 1980. By 2000, the # of people per square mile had grown to 76. This information was used to develop a linear equation in slope intercept form, given below, where x is the time in years and y is the population density. Think of 1980 as year zero. what is the population density expected to be in 2018? y = 1/2x + 66

Answer 1

Determine the value of x for taking 1980 as 0.

`\begin{gathered} x=2018-1980 \\ =38 \end{gathered}`

The equation is y = 1/2x + 66.

Substitute the value of x in the equation to determine the population density in 2018.

`\begin{gathered} y=(1)/(2)\cdot38+66 \\ =19+66 \\ =85 \end{gathered}`

So population density in year 2018 is 85.

Answer: 85