Quadrilateral jklm has side lengths of jk = 3y + 4, kl = 8x – 12, lm = 5y – 6, and jm = 4x + 20. find the values of x and y that make quadrilateral jklm a parallelogram. a. x = 8, y = 11 b. x = 7, y = 5 c. x = 8, y = 6 d. x = 8, y = 5 (geometry)