Evaluating a function expression

We're asked to evaluate
negative 2 times f of negative 6

plus g of 1.

And they've defined,
at least graphically,

f of x and g of x here below.

So let's see how we
can evaluate this.

Well, to do this, we
first have to figure out

what f of negative 6 is.

So our input into our
function is negative 6.

And we'll assume that's
along the horizontal axis.

So our input is negative 6.

And based on our function
definition, f of negative 6

is 7.

So this thing.

Let me write this down. f
of negative 6 is equal to 7.

And what is g of 1?

Well, once again,
here's our input axis.

And then the function
says that g of 1,

which is right over
there, is negative 5.

g of 1 is equal to negative 5.

So this statement simplifies
to negative 2 times

f of negative 6, which is 7.

So times 7 plus g of
1, which is negative 5.

So plus negative 5, which
simplifies to-- let's see.

Negative 2 times 7 is
negative 14 plus negative 5,

which is negative 19.

And we are done.