Here is some proof that it not an actual exam just a regular class work assignment? What I went over and that what I have to do because I didn't finish it :(

What is the value of x when x + 7 = 21?

If f(x) = 4x - 3 and g(x) = x + 4, find (f - g) (x)

Aline is perpendicular to another line m2= (-1/m1), where m1 is the slope of the original line and m2 is the slope of the perpendicular line. which of the following equations represents the line that passes through the point (-2,1) and is perpendicular to the line below?