(x+2)dy+(y-1)dx=0

Solution for (x+2)dy+(y-1)dx=0 equation:

Simplifying
(x + 2) * dy + (y + -1) * dx = 0

Reorder the terms:
(2 + x) * dy + (y + -1) * dx = 0

Reorder the terms for easier multiplication:
dy(2 + x) + (y + -1) * dx = 0
(2 * dy + x * dy) + (y + -1) * dx = 0

Reorder the terms:
(dxy + 2dy) + (y + -1) * dx = 0
(dxy + 2dy) + (y + -1) * dx = 0

Reorder the terms:
dxy + 2dy + (-1 + y) * dx = 0

Reorder the terms for easier multiplication:
dxy + 2dy + dx(-1 + y) = 0
dxy + 2dy + (-1 * dx + y * dx) = 0
dxy + 2dy + (-1dx + dxy) = 0

Reorder the terms:
-1dx + dxy + dxy + 2dy = 0

Combine like terms: dxy + dxy = 2dxy
-1dx + 2dxy + 2dy = 0

Solving
-1dx + 2dxy + 2dy = 0

Solving for variable 'd'.

Move all terms containing d to the left, all other terms to the right.

Factor out the Greatest Common Factor (GCF), 'd'.
d(-1x + 2xy + 2y) = 0

Subproblem 1
Set the factor 'd' equal to zero and attempt to solve:

Simplifying
d = 0

Solving
d = 0

Move all terms containing d to the left, all other terms to the right.

Simplifying
d = 0
Subproblem 2
Set the factor '(-1x + 2xy + 2y)' equal to zero and attempt to solve:

Simplifying
-1x + 2xy + 2y = 0

Solving
-1x + 2xy + 2y = 0

Move all terms containing d to the left, all other terms to the right.

Add 'x' to each side of the equation.
-1x + 2xy + x + 2y = 0 + x

Reorder the terms:
-1x + x + 2xy + 2y = 0 + x

Combine like terms: -1x + x = 0
0 + 2xy + 2y = 0 + x
2xy + 2y = 0 + x
Remove the zero:
2xy + 2y = x

Add '-2xy' to each side of the equation.
2xy + -2xy + 2y = x + -2xy

Combine like terms: 2xy + -2xy = 0
0 + 2y = x + -2xy
2y = x + -2xy

Add '-2y' to each side of the equation.
2y + -2y = x + -2xy + -2y

Combine like terms: 2y + -2y = 0
0 = x + -2xy + -2y

Simplifying
0 = x + -2xy + -2y

The solution to this equation could not be determined.

This subproblem is being ignored because a solution could not be determined.
Solution
d = {0}