[tex]f(x) = 6x+2[/tex]
A.
To evaluate f(8), we substitute x with 8 in our expression.
[tex]f(8) = 6*8 + 2\\f(8) = 48 +2\\f(8) = 50[/tex]
Answer: f(8) = 50
B.
To evaluate f(x+6), we do the same but substitute x with x+6 instead.
[tex]f(x+6) = 6(x+6) + 2[/tex]
Expand the parenthesis by multiplying 6 with x and 6.
[tex]f(x+6) = 6x + 6*6 + 2\\f(x+6) = 6x+36+2\\f(x+6) = 6x+38[/tex]
Answer: f(x+6) = 6x + 38
C.
Again, we're doing the same thing, just substituting x with -x.
[tex]f(-x) = 6 * (-x) + 2\\ f(-x)=-6x+2[/tex]
Answer: f(-x) = -6x+2
