Please help with geometry eoc review

Graph a triangle (xyz) and reflect it over the line y=x to create triangle x’y’z’. describe the transformation using words. draw a line segment from point x to the reflecting line, and then draw a line segment from point x’ to the reflecting line. what do you notice about the two line segments you drew? do you think you would see the same characteristics if you drew the line segment connecting y with the reflecting line and then y’ with the reflecting line? how do you know?

Which is the value of this expression when p=3 and q=-9

Ireally don't understand this, i'm really an idiot but i want to know how to figure this out. !