Has at least one right angle but is not a square

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?

F(x)=x/2-2 and g(x)=2x^2+x-3 find (f+g)(x)

F(x) = 1/x g(x)=x-4 can you evaluate (g*f)(0) ? why or why not?