Answer:
x = 20
Step-by-step explanation:
The sum of the angles in a triangle is 180. A right triangle has one angle of 90. Thus, the sum of the other two angles will be 90. So, 90+31 = 121 and 180-121 = 59. (3x-1) = 59. Solve for x. This would mean that x would be 20. 3*20 = 60 and 60-1 = 59. All the angles add together would get 180: 59+90+31.
