Ihave a question. in my class we are doing a new unit and i don't understand it. we are solving systems of equations by graphing. i don't understand how to graph each point for both equations and how they intersect each other.

there is an example:
{ x+y=8
x-y=4

The average number of vehicles waiting in line to enter a parking lot can be modeled by the function f left parenthesis x right x squared over 2 left parenthesis 1 minus x right parenthesis endfraction , where x is a number between 0 and 1 known as the traffic intensity. find the rate of change of the number of vehicles waiting with respect to the traffic intensity for the intensities (a) xequals0.3 and (b) xequals0.6.

If f(x) and g(x) are inverse functions of each other, which of the following shows the graph of f(g(x)

The given diagram shows the parts of a right triangle with an altitude to the hypotenuse. using the two given  measures, find the other four.