Answer:
The linear function is:
[tex]f(x) = -\frac{1}{3}x-\frac{23}{3}\\[/tex]
Step-by-step explanation:
Given
f(-1)=8 and f(5)=6
We can extract two pairs of input-output from the values given
From f(-1)=8,
(x1,y1) = (-1,8)
and
From f(5)=6
(x2,y2) = (5,6)
The linear function is given by:
[tex]y = mx+b[/tex]
Here m is the slope which is calculated by the formula
[tex]m =\frac{y_2-y_1}{x_2-x_1}[/tex]
Putting values
[tex]m = \frac{6-8}{5+1}\\m = \frac{-2}{6}\\m = -\frac{1}{3}[/tex]
Putting in the equation
[tex]y = -\frac{1}{3}x+b[/tex]
Putting the pair of input-output equation (5,6)
[tex]6 = -\frac{1}{3}(5) +b\\6 = -\frac{5}{3}+b\\b = 6+\frac{5}{3}\\b = \frac{18+5}{3}\\b = \frac{23}{3}[/tex]
Putting the value of b
[tex]y = -\frac{1}{3}x-\frac{23}{3}\\f(x) = -\frac{1}{3}x-\frac{23}{3}\\[/tex]
Hence,
The linear function is:
[tex]f(x) = -\frac{1}{3}x-\frac{23}{3}\\[/tex]