Answer:
Below
Step-by-step explanation: This is all i can do.
I hope it helps :)
1.
[tex]Sum\:of\:angles\:in\:a\:triangle = 180\\\\(3x+9)+(5x-1)+(4x+4) = 180\\ 3x+9+5x -1+4x+4=180\\\\Collect\:like\:terms\\3x+5x+4x+9-1+4=180\\12x+12=180\\12x = 180-12\\12x=168\\\\Divide\:both\:sides\:of\:the\:equation\:by\:12\\\frac{12x}{12} = \frac{168}{12} \\\\x = 14[/tex]
2.
