Given two points (x1, y1) and (x2, y2) on the Cartesian plane, then the distance, d, between the two points is given by
[tex]\begin{gathered} d=y_2-y_1,\text{ if }x_1=x_2 \\ \text{ OR} \\ d=x_2-x_1,\text{ if }_{}y_1=y_2_{} \end{gathered}[/tex]
For the points (-1, 1) and (1, 1)
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