They were supposed to have covered this material before assigning homework on it. Are you needing lesson instruction?
When you reply, please provide a corrected statement of the exercise. (No quadratic can be "expressed in the form (ax + b)", because "(ax + b)*(2 + c)" [which is my guess as to what the two strings of characters mean] isn't a quadratic. The original exercise probably actually asked for something more along the lines of "a(x + b)2 + c".) Thank you!