What must be true for lines a and b to be parallel lines? Select four options. Lines a and b are crossed by transversals c and d. The angles formed by lines a, c, and d, clockwise from top left, are (3 x minus 1) degrees, 2, blank, blank, blank, 1. The angles formed by lines b and c are blank, (4 x minus 10) degrees, blank, blank. The angles formed by lines b and d are 58 degrees, blank, blank, blank. mAngle1 = (4 x minus 10) degrees mAngle2 = 58Degrees x = 20 (3 x minus 1) degrees equals = (4 x minus 10) degrees Angle1 = 58Degrees (3 x minus 1) degrees equals = 58Degrees x = 19 (3 x minus 1) degrees + (4 x minus 10) degrees + mAngle2 = 180Degrees