F (x) = 1/8x+3

g (x) = 12-5x

Write f (g (x)) as an expression in terms of x

Normally if you want to get the f (3) you would replace every x value by in. For this question you have to change each x value to the g (x) value. g (x) = 12-5x, which means you can replace the g (x) by 12-5x in the f (g (x)).

f (g (x)) = f (12-5x)

f (12-5x) = 1/8 (12-5x) + 3

f (12-5x) = 1.5 - 0.628x + 3

f (12-5x) = 0.628x + 3.5

f (g (x)) = 0.628x + 3.5