Questions on the images

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)

Which of these tools or constructions is used to inscribe a hexagon inside a circle?

The construction of copying qpr is started below. the next step is to set the width of the compass to the length of ab. how does this step ensure that a new angle will be congruent to the original angle? by using compass take the measures of angle and draw the same arc according to it.