recall, f plus g of x is equal to f of x plus g of x
[tex](f+g)(x) = f(x)+g(x)[/tex]
[tex](f+g)(x)=10x+5 + 3x+6 = 13x + 11[/tex]
[tex](f+g)(-1) = 13(-1)+11=-2[/tex]
recall the nested composite functions, f of g of x, the input for function f, is the result of function g(x)
[tex]f(x)=6x+6[/tex]
[tex]f(g(x))=f(5x+9)=6(5x+9)+6 = 30x + 60[/tex]
[tex]f(g(2))=30(2)+60=120[/tex]
