We're looking for a solution of the form 
. By the chain rule, this solution should have total differential
and the equation is exact if the mixed second-order partial derivatives of 
are equal, i.e. 
.
The given ODE is exact, since
Then
With 
, we get
240 each 10 percent is 30 calories multiply them by ten gets you 300
Using the slope-intercept form, the slope is -2.
