Define a function that when passed the coordinates of two points (x1, y1) and (x2, y2) through which a line passes and another value (y3), returns the x-coordinate of the point on the line when y = y3.

You may assume the line is not vertical (because then we'll need conditions).

Just like the perimeter function (https://codingbat.com/prob/p244438), the complexity of this question is in the research and analysis, not the implementation.

You may assume the x-coordinate corresponding to y3 is an integer. That is, the line passes through (x3, y3) where x3 and y3 are both integers.