Can someone answer these 3 questions ASAP

With number 11 ( show how you got the answer)

Is there a direction u in which the rate of change of f(x, y)equals=x squared minus 3 xy plus 4 y squaredx2−3xy+4y2 at p(1,2) equals 14? give reasons for your answer. choose the correct answer below. a. no. the given rate of change is smaller than the minimum rate of change. b. no. the given rate of change is larger than the maximum rate of change. c. yes. the given rate of change is larger than the minimum rate of change and smaller than the maximum rate of change.

Matt had 5 library books. he checked out 1 additional book every week without retuening any books. whats the matching equation