May you help me and explain to me please.

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

Abag contains 4 red, 7 blue and 5 yellow marbles. event a is defined as drawing a yellow marble on the first draw and event b is defined as drawing a blue marble on the second draw. if two marbles are drawn from the bag, one after the other and not replaced, what is p(b|a) expressed in simplest form? a. 7/16 b. 7/15 c. 14/16 d. 14/15

If the discriminant if a quadratic equation is 4 which statement describes the roots?