I can't make out (a), but here's (b).....
g(f(-2)).......let's look at the f(-2) part, first.....this says to look for the associated y value where the x value for "f" = -2
So..... we go to x = -2 on the graph and look at the y value there for the graph of "f"...this is = 1 .......so f(-2) = 1 ....this makes sense.......(-2, 1) is a point on "f".......when x = -2, y = 1 ....!!!
And now we have g(f(-2)) = g(1)
And now we do the same thing, again.....we look at the graph of g where x = 1 and find the associated y value.....so......when the x value for "g" = 1, the associated y value = 5
And 5 is your final answer.......!!!
Hope this helps......!!!!
