In this picture, m∠AOC = 69° and m∠COD = (2x + 4)°. If ∠AOC and ∠COD are complementary angles, then what is the value of x?
If two angles are complementary, their sum is 90 degrees.
Therefore, m∠AOC + m∠COD = 69° + (2x + 4)° = 90°.
Combining like terms, we get 2x + 73 = 90.
Subtracting 73 from both sides, we get 2x = 17.
Dividing both sides by 2, we get x = <<8.5=8.5>>8.5.
Therefore, the value of x is 8.5. Answer: \boxed{8.5}.