From the question
We are given the function
[tex]y=-0.5x+29[/tex]
Comparing the function with the equation
[tex]y=mx+c[/tex]
Then the slope of the function is
m = - 0.5
Using the function
[tex]y=-0.5x+29[/tex]
When x = 1
[tex]\begin{gathered} y=-0.5(1)+29 \\ y=28.5 \end{gathered}[/tex]
When x = 2
[tex]\begin{gathered} y=-0.5(2)+29 \\ y=28 \end{gathered}[/tex]
When x = 3
[tex]\begin{gathered} y=-0.5(3)+29 \\ y=27.5 \end{gathered}[/tex]
By comparing the values of y, we will notice a decrease of 0.5
Hence,
The value of the function decreased by 0.5 per year after 1990
