Answer:
[tex](3x + 6) + (x + 10) = 90(being \: complementary \: angle) \\ \\3x + 6 + x + 10 = 90 \\ 4x + 16 = 90 \\ 4x = 90 - 16 \\ x = \frac{74}{4} \\ x = 18.5[/tex]
