Explanation:
Here's how you can solve it if you have the equation of the line. Parallel lines have the same slope but different y-intercepts, meaning that if the equation of the line is in standard form, y = mx + b, then the m's are the same but the b's are different. To find the equation plug in the point (2,3) into whatever the original equation of the line is, (for demonstration purposes I am going to use m = 2 and b = 1). So....
3 = 2(2) + 1
But instead of solving it and proving it is true, take out the 1 and solve. (If you were to try to solve for it with the original b it would prove to be a false statement.)
So you actually have this equation.
3 = 2(2) + b
Now solve for b and plug that into the new equation. In this case, using the numbers I made up the parallel line would have the equation of y = 2x - 1.