Pls answer number 20 i will mark brainliest

Find the directions in which the function increases and decreases most rapidly at upper p 0p0. then find the derivatives of the function in these directions. f(x,y)equals=x squared plus xy plus y squaredx2+xy+y2, upper p 0p0left parenthesis 1 comma negative 4 right parenthesis

The taxi fare in gotham city is $2.40 for the first 1 2 12 mile and additional mileage charged at the rate $0.20 for each additional 0.1 mile. you plan to give the driver a $2 tip. how many miles can you ride for $10?

Is (root2 -2)^2 rational or irrational. show the steps and answer fast