To find w, you subtract 117 from 180. After that you get w = 63. Now you add 63 and 31 to get 94. You then subtract 94 from 180 to get x = 86. Now you add 86 and 56 to get 142. You then subtract 142 from 180 to get y = 38. Now you add 38 and 117 to get 155. Again you subtract 155 from 180 to get z = 25