The coordinates of the vertices of △RST are R(−3,1), S(−1,4), and T(3,1) .
Which statement correctly describes whether △RST is a right triangle?
△RST is a right triangle because RS¯¯ is perpendicular to RT¯¯ .
△RST is a right triangle because RS¯¯ is perpendicular to ST¯¯ .
△RST is a right triangle because ST¯¯ is perpendicular to RT¯¯.
△RST is not a right triangle because no two of its sides are perpendicular.