Let x be an variable.
\Find the point that is the same distance from
3.8 and 4.2 i.e. mid point between
3.8 and 4.2.
Mid point "M" = 
Mid point between
3.8 and 4.2 is 0.2.
The distance from
3.8 to 0.2 is 4 units.
The distance from 0.2 to 4.2 is 4 units.
\So the equation is
.
Graph of the equation on a number line.
\
The equation is
.