First of all, let's find the slope of line L. To find the slope of a line, you write it in the explitic form , and consider the coefficient
. So, we have
So, the slope of line L is 2/3.
Two lines are parallel if they have the same slope. So, line M has slope 2/3 as well, and we know that it passes through the point (3, -10).
When you are given the slope and a point
of a line, its equation is given by
So, if you plug your values, you have
which you can simplify into