Answer:
c = 112 , d = 29
Explanation:
c and 68 are a linear pair and sum to 180° , that is
c + 68 = 180 ( subtract 68 from both sides )
c = 112
the 3 angles 30, 3d - 5 and 68 lie on straight line AOB and sum to 180° , so
30 + 3d - 5 + 68 = 180
3d + 93 = 180 ( subtract 93 from both sides )
3d = 87 ( divide both sides by 3 )
d = 29