First, we need to take the equation x + 5y = 10 and solve for y as:
Since the coefficient of x is -1/5, the slope of this function is -1/5 and the slope of a parallel line is also -1/5.
Then, with the slope m and a point (x1, y1), we can find the equation of a line as:
So, replacing m by -1/5 and (x1, y1) by (1, 3), we get:
Answer: y = -(1/5)x + (16/5)