As shown in the figure :
The sum of the central angles = 360
so,
[tex](x+55)+(2x-71)+(x-3)+55=360[/tex]
Solve the equation for x :
[tex]\begin{gathered} x+55+2x-71+x-3+55=360 \\ 4x+36=360 \\ 4x=360-36 \\ 4x=324 \\ \\ x=\frac{324}{4}=81 \end{gathered}[/tex]
So, the answer is : x = 81
