2x - 4b + 7a + 5c

Start with the equation:

$$2x - 4b + 7a + 5c = 0$$

Isolate the term with $x$ by moving the other terms to the right side:

$$2x = 4b - 7a - 5c$$

Divide both sides by 2:

$$x = \frac{4b - 7a - 5c}{2}$$ $$x = 2b - \frac{7}{2}a - \frac{5}{2}c$$

Start with the equation:

$$2x - 4b + 7a + 5c = 0$$

Isolate the term with $b$ by moving the other terms to the right side:

$$-4b = -2x - 7a - 5c$$

Multiply both sides by $-1$ to make the $b$ term positive:

$$4b = 2x + 7a + 5c$$

Divide both sides by 4:

$$b = \frac{2x + 7a + 5c}{4}$$ $$b = \frac{1}{2}x + \frac{7}{4}a + \frac{5}{4}c$$

Start with the equation:

$$2x - 4b + 7a + 5c = 0$$

Isolate the term with $a$ by moving the other terms to the right side:

$$7a = -2x + 4b - 5c$$

Divide both sides by 7:

$$a = \frac{-2x + 4b - 5c}{7}$$ $$a = -\frac{2}{7}x + \frac{4}{7}b - \frac{5}{7}c$$

Start with the equation:

$$2x - 4b + 7a + 5c = 0$$

Isolate the term with $c$ by moving the other terms to the right side:

$$5c = -2x + 4b - 7a$$

Divide both sides by 5:

$$c = \frac{-2x + 4b - 7a}{5}$$ $$c = -\frac{2}{5}x + \frac{4}{5}b - \frac{7}{5}a$$

The solutions are:
$\boxed{x = 2b - \frac{7}{2}a - \frac{5}{2}c}$
$\boxed{b = \frac{1}{2}x + \frac{7}{4}a + \frac{5}{4}c}$
$\boxed{a = -\frac{2}{7}x + \frac{4}{7}b - \frac{5}{7}c}$
$\boxed{c = -\frac{2}{5}x + \frac{4}{5}b - \frac{7}{5}a}$