Answer:
neither!
Step-by-step explanation:
Answer:
c = 40d+20
Step-by-step explanation:
He has to pay 20 dollars and that can't multiply so the forty has to multiply and it would have to be by d because c is the total cost
Answer:


Step-by-step explanation:
First we define two generic vectors in our
space:


By definition we know that Euclidean norm on an 2-dimensional Euclidean space
is:

Also we know that the inner product in
space is defined as:

So as first condition we have that both two vectors have Euclidian Norm 1, that is:

and

As second condition we have that:


Which is the same:

Replacing the second condition on the first condition we have:

Since
we have two posible solutions,
or
. If we choose
, we can choose next the other solution for
.
Remembering,

The two vectors we are looking for are:
