Please answer this correctly

The variable in a relation who’s value depends on the value of the independent variable is called what?

Which of the following expressions is equal to 2x^2+8

Lindsay used two points, (x,y; ) and (+2.82), to find the equation of the line, y = mx + b, that passes through the points. y2-y, first, she used the definition of slope and determined that the value of mis x, - . given this information, which expression must represent the value of b?