Hello!
Complementary angles mean they add to 90
Since a and b are complementary we can use the equation
a + b = 90
Put in the values you know
40 + b = 90
Subtract 40 from both sides
b = 50
supplementary means they add to 180
Since B and C are supplementary we can use the equation
B + C = 180
Put in the values you know
50 + c = 180
subtract 180 from both sides
c = 130
The answers are b = 50 and c = 130
Hope this helps!