Lee cada situacion y escribe la razon correspondiente

Aboat has a speed of 9 mph in calm water. it takes the boat 4 hours to travel upstream but only 2 hours to travel the same distance downstream. which equation can be used to find c, the speed of the current? 2(9 – c) = 4(9 + c) 9 + c = 4(9 – c) 9 – c = 2(9 + c) 4(9 – c) = 2(9 + c)

Find the derivative of the function

X+ 4y − z = −14 5x + 6y + 3z = 4 −2x + 7y + 2z = −17