# suggested substitution

## Substitution Suggested by the Equation | Bernoulli's Equation

**Substitution Suggested by the Equation**

Example 1

The quantity (2x - y) appears twice in the equation. Let

$z = 2x - y$

$dz = 2~dx - dy$

$dy = 2~dx - dz$

Substitute,

$(z + 1)~dx - 3z(2~dx - dz) = 0$

then continue solving.