the answer is x=12
start by checking what the angles are, in this case they are not equal, but they do add up to 180. so plug what you know into an equation.
(4x+8) + (9x+16) = 180
then separate the common terms
4x+8+9x+16=180
then add the like terms together
13x+ 24=180
subtract 24 from 180 to get the x variable alone
13x= 156
then divide each side by 13 to get the x value, which is twelve.
x=12