Use the Limit Definition of the Partial Derivative to Compute $\text { Find } \frac { \partial f } { \partial y } \text { at the point } ( - 10,9 ) \text { : } f ( x , y ) = 5 x ^ { 2 } + 7 x y + 7 y ^ { 2 }$

Essay

Use the limit definition of the partial derivative to compute the indicated partial derivative of the function at the specified point.
- $\text { Find } \frac { \partial f } { \partial y } \text { at the point } ( - 10,9 ) \text { : } f ( x , y ) = 5 x ^ { 2 } + 7 x y + 7 y ^ { 2 }$