In ΔRST, \text{m}\angle R = (5x-11)^{\circ}m∠R=(5x−11)

, \text{m}\angle S = (3x-3)^{\circ}m∠S=(3x−3)

, and \text{m}\angle T = (3x+18)^{\circ}m∠T=(3x+18)

. Find \text{m}\angle R.m∠R.