Answer:
x = 9
Step-by-step explanation:
By remote exterior angle theorem:
[tex](12x + 14)\degree = (1 + 5x) \degree+ 76 \degree \\ 12x + 14 = 1 + 5x + 76 \\ 12x - 5x = 77 - 14 \\ 7x = 63 \\x = \frac{63}{7} \\ \huge \red{ \boxed{ x = 9}}[/tex]
