In the following figure, find the value of x

Dear student,

Here is the solution of your asked query:
$$\begin{gathered} 3x+3x+150+x=360 \\ \Rightarrow 7x+150=360 \\ \Rightarrow 7x=360-150 \\ \Rightarrow 7x=210 \\ \Rightarrow x=\frac{210}{7}=30 \end{gathered}$$
Regards