Write down the equation of a line parallel to x - 2y + 8 = 0 and passing through the point (1, 2).

Given equation of line,

x - 2y + 8 = 0.

Converting in the form of y = mx + c,

⇒ 2y = x + 8

⇒ y = $\dfrac{1}{2}x + 4$

Comparing we get,

Slope = $\dfrac{1}{2}$

Line parallel to x - 2y + 8 = 0 will have the same slope.

Equation of the line having slope $\dfrac{1}{2}$ and passing through (1, 2) can be given by point-slope form i.e.,

$\Rightarrow y - y$1 = m(x - x1) \\[1em] \Rightarrow y - 2 = \dfrac{1}{2}(x - 1) \\[1em] \Rightarrow 2(y - 2) = x - 1 \\[1em] \Rightarrow 2y - 4 = x - 1 \\[1em] \Rightarrow x - 2y + 3 = 0.

Hence, the equation of the required line is x - 2y + 3 = 0.