One angle measures 27°, and another angle measures (8d − 9)°. If the angles are complementary, what is the value of d?
a) d = 72
b) d = 21
c) d = 3
d) d = 9
Since the angles are complementary, the sum of the measures of the two angles is 90 degrees.
Therefore, 27 + (8d - 9) = 90.
Simplifying this equation, we have 8d + 18 = 90.
Subtracting 18 from both sides, we get 8d = 72.
Dividing both sides by 8, we find that d = 9.
So, the value of d is 9.
Therefore, the answer is d) d = 9.