Question

What is the equation of a line that passes through the point (5, −4) and is parallel to the line whose equation is 2x + 5y = 10?

Answer 1

A quick way to solve this problem involves copying the given equation:

2x + 5y = 10

dropping the final 10, and
substituting the given x and y values:  (5, -4).  

Then:

2(5) + 5(-4) = C           C = 10-20 = -10

Thus, the equation of this new, parallel line is 2x + 5y = -10.