The correct formula to find the distance \( D \) between two points \( (x_1, y_1) \) and \( (x_2, y_2) \) in a coordinate plane is:
\[ D = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \]
So, the right choice from the options provided is:
D = \(\sqrt{(x_2−x_1)^2+(y2 − y1)^2}\)