b) Hence determine the number of sides of the polygon. Two lines have equations: L1: 3x – 4y + 12 = 0 and L2: 6x + 8y – 5 = Express each line in the form y = mx + c.

From part a) (solved previously), we found that $x = 30$. The exterior angle of the polygon is $x^\circ$, so the exterior angle is $30^\circ$.

For any regular polygon, the sum of its exterior angles is $360^\circ$. The number of sides ($n$) is found by dividing $360^\circ$ by the measure of one exterior angle.

The number of sides of the polygon is $\boxed{12}$.

Express each line in the form $y = mx + c$.

For L1: $3x - 4y + 12 = 0$

Subtract $3x$ and 12 from both sides of the equation.

Divide every term by $-4$.

The equation for L1 in the form $y = mx + c$ is $\boxed{y = \frac{3}{4}x + 3}$.

For L2: $6x + 8y - 5 = 0$

Subtract $6x$ and add 5 to both sides of the equation.

Divide every term by 8.

The equation for L2 in the form $y = mx + c$ is $\boxed{y = -\frac{3}{4}x + \frac{5}{8}}$.