Find dydt for the equation below.

7x3+7y3=9

dy/dt = - x^2/y^2 dx/dt

Step-by-step explanation:

7x^3 + 7y^3 = 0

Take the derivative with respect to t

7 * 3x^2 dx/dt + 7 * 3y^2 dy/dt = 0

21 x^2 dx/dt + 21 y^2 dy/dt = 0

Divide each side by 21

x^2 dx/dt + y^2 dy/dt = 0

Subtract x^2 dx/dt from each side

x^2 dx/dt - x^2 dx/dt+y^2 dy/dt = - x^2 dx/dt

y^2 dy/dt = - x^2 dx/dt

Divide each side by y^2

y^2 / y^2 dy/dt = - x^2/y^2 dx/dt

dy/dt = - x^2/y^2 dx/dt

y=-1

Step-by-step explanation:

I thought the unknown space between 7y and 3 was multiplication so here is my work.

7*3+7y*3

21+7*-1*3

=9