4. Find the domain I've got no clue, the lesson made no sense to me either.

See below.

Step-by-step explanation:

The domain is simply the range of x-values the graph encompasses. From the given graph, we can see that the graph stretches from x=-4 to x=+4.

However, note that the graph does not include -4 since the point is an open circle. However, it does include +4 since the point is a closed circle. Therefore, the domain of this graph is:

In interval notation:

(Parenthesis on the left because -4 is not included. Brackets on the right because +4 is included.)

30 units^2

step-by-step explanation:

area is l × w

the length is 3

and the width is 10

3 × 10= 30 units squared