The two points already given are 8 units apart, so the third point would have to be either 8 units upward or 8 units downward. Now for an equilateral triangle, the x-coordinate has to be a number between the x-coordinates of the points already given, in this case, -2 and 6. On a coordinate plane, the middle x-value is 2. Therefore, the ordered pairs that make the most possible coordinates of vertex R are (2,8) or (2,-8) depending on whether you want the point of the triangle to face upward or for it to face downward.
