Answer
$1.8$
Work Step by Step
In the case of two parallel lines we can choose any point along either one and apply the given formula, for the example I will pick point (0, 2.5) on line $3x - 4y = 10$.
Now we transcribe the other equation so that it equals 0:
$3x + 4y - 1 = 0$
You can read in the equation that:
$A = 3$
$B = 4$
$C = -1$
You can read in the coordinates that:
$x_{1} = 0$
$y_{1} = 2.5$
Enter this information in the given formula:
$\frac{|Ax_{1} + By_{1} + C|}{\sqrt {A^{2} + B^{2}}}$
$\frac{|3 * 0 + 4 * 2.5 - 1|}{\sqrt {3^{2} + 4^{2}}} = 1.8$
