Basically the h(0) or whatever number is in the parenthesis just means if h was a certain number, what would the output be?
So in the graph, you have points scattered all over the place. We will take the one right under the -7 on the x axis. That is saying if if h was -7, what will its output be? -7 is the domain or the x value, and the output would be the range or the y value, which in this case is -2. I hope this helps!
The perimeter of a rectangle is P = 2 b + 2 h , where is the base (or width) and is the height (or length). If a rectangle is a square, with sides of length , the formula for perimeter is P s q u a r e = 2 s + 2 s = 4 s and the formula for area is A s q u a r e = s ⋅ s = s 2